Calcium hypochlorite.docx

Calcium hypochloriteFrom Wikipedia, the free encyclopedia

Calcium hypochlorite or Calcium oxychloride

Other names[hide]

Hypochlorous acid, calcium salt

Bleaching powder, Calcium oxychloride

Identifiers

CAS number 7778-54-3 

ChemSpider 22912 

EC number 231-908-7

UN number 1748

RTECS number NH3485000

Jmol-3D images Image 1

SMILES

[show]

InChI

[show]

Properties

Molecular formula Ca(ClO)2

Molar mass 142.98 g/mol

Appearance white/gray powder

Density 2.35 g/cm3 (20 °C)

Melting point100 °C

Boiling point175 °C, decomposes

Solubility inwater 21 g/100 mL, reacts

Solubility reacts in alcohol

Hazards

MSDS ICSC 0638

EU Index 017-012-00-7

EU classification Oxidant (O)

Corrosive (C)

Harmful (Xn)

Dangerous for the environment (N)

R-phrases R8, R22, R31, R34, R50

S-phrases (S1/2), S26, S36/37/39, S45,S61

NFPA 704

031

OX

Flash point Non-flammable

LD50 850 mg/kg (oral, rat)

Related compounds

Other anions Calcium chloride

Other cations Sodium hypochlorite

   (verify) (what is:  / ?)

Except where noted otherwise, data are given for materials in their standard

state (at 25   °C, 100   kPa)

Infobox references

Calcium hypochlorite is a chemical compound with formula Ca(Cl O )2. It is widely used for water treatment and as

a bleaching agent. This chemical is considered to be relatively stable and has greater available chlorine than sodium

hypochlorite (liquid bleach).

Contents

  [hide] 

1 Preparation

2 Properties

3 Uses

4 Safety

5 References

6 External links

Preparation[edit source | editbeta]

It is manufactured by the calcium process:

.

"Bleaching powder" is a mixture of calcium hypochlorite (Ca(OCl)2) and the

basic chloride CaCl2, H2O with some slaked lime, Ca(OH)2. [1]

Properties[edit source | editbeta]

Calcium hypochlorite is a yellow white solid which has a strong smell

of chlorine. It is not highly soluble in water and is more preferably used in soft

to medium-hard water. It has two forms: dry and hydrated. The hydrated form is

safer to handle.

Calcium hypochlorite reacts with carbon dioxide to form calcium carbonate and

release dichlorine monoxide:

.

A calcium hypochlorite solution is basic. This is due to

the hydrolysis performed by the hypochlorite ion, as hypochlorous

acid is weak, but calcium hydroxide is a strong base. As a result, the

hypochlorite ion is a strong conjugate base, and the calcium ion is a weak

conjugate acid:

ClO−

 + H2O → HClO + OH−

Similarly, calcium hypochlorite reacts with hydrochloric acid to

form calcium chloride, water and gaseous chlorine:

Ca(OCl)2 + 4 HCl → CaCl2 + 2 H2O + 2 Cl2

Uses[edit source | editbeta]

Calcium hypochlorite is used for the disinfection of drinking water

or swimming pool water. It is used as a sanitizer in outdoor

swimming pools in combination with acyanuric acid stabilizer,

which reduces the loss of chlorine due to ultraviolet radiation.

The calcium content hardens the water and tends to clog up

some filters; hence, some products containing calcium

hypochlorite also contain anti-scaling agents.

Calcium hypochlorite is an ingredient in bleaching powder, used

for bleaching cotton and linen. It is used in bathroom cleaners,

household disinfectant sprays, moss and algae removers, and

weedkillers.

In addition, calcium hypochlorite may be used to

manufacture chloroform.

Bleaching powder is used in the sugar industry for bleaching

sugar cane juice before its crystallization.

Safety[edit source | editbeta]

Calcium hypochlorite is best kept in a cool dry place away from

any organic material. It is known to undergo self heating and

rapid decomposition accompanied by the release of toxic

chlorine gas.[citation needed]

References[edit source | editbeta]

1. ̂  Pradyot Patnaik. Handbook of Inorganic Chemicals.

McGraw-Hill, 2002, ISBN 0-07-049439-8

External links[edit source | editbeta]

Chemical Land

V

T

E

Calcium

Categories: 

Antiseptics

Bleaches

Hypochlorites

Calcium compounds

Oxidizing agents

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Sodium bicarbonateFrom Wikipedia, the free encyclopedia

Sodium bicarbonate

IUPAC name [hide]

Sodium hydrogen carbonate

Other names[hide]

Baking soda, bicarbonate of soda, nahcolite, sodium bicarbonate, sodium

hydrogencarbonate

Identifiers

CAS number 144-55-8 

PubChem 516892

ChemSpider 8609 

UNII 8MDF5V39QO 

EC number 205-633-8

DrugBank DB01390

KEGG C12603 

MeSH Sodium+bicarbonate

ChEBI CHEBI:32139 

ChEMBL CHEMBL1353 

RTECS number VZ0950000

ATC code B05 CB04 ,B05 XA02 ,QG04 BQ01

Beilstein Reference 4153970

Jmol-3D images Image 1

SMILES

[show]

InChI

[show]

Properties

Molecular formula NaHCO

3

Molar mass 84.007 g mol−1

Appearance White crystals

Odor odorless

Density 2.20 g cm−3[1]

Melting point50 °C, 323 K, 122 °F (decomposes to sodium

carbonate)

Solubility in water 9 g/100 mL

69 g/L (0 °C)[2]

96 g/L (20 °C)[3]

165 g/L (60 °C)[3]

236 g/L (100 °C)[2]

Solubility Soluble[vague] in acetone, insoluble inethanol

log P -0.82

Acidity (pKa) 10.329[4]

6.351 (carbonic acid)[4]

Refractive index (nD) 1.3344

Pharmacology

Routes of

administration

Intravenous, oral

Thermochemistry

Std enthalpy of

formation ΔfHo298

−948 kJ·mol−1[5]

Standard molar

entropy So298

102 J·mol−1·K−1[5]

Hazards

MSDS External MSDS

Main hazards Causes serious eye irritation

NFPA 704

0

10

LD50 4.22 g kg−

Related compounds

Other anions Sodium carbonate

Other cations Ammonium bicarbonate

Potassium bicarbonate

Related compounds Sodium bisulfate

Sodium hydrogen phosphate

   (verify) (what is:  / ?)

Except where noted otherwise, data are given for materials in their standard

state (at 25   °C, 100   kPa)

Infobox references

Sodium bicarbonate or sodium hydrogen carbonate is the chemical compound with the formula Na HCO 3. Sodium

bicarbonate is a white solid that is crystalline but often appears as a fine powder. It has a slightly salty, alkaline taste

resembling that of washing soda (sodium carbonate). The natural mineral form is nahcolite. It is a component of the

mineral natron and is found dissolved in many mineral springs. It is among the food additives encoded by European

Union, identified by the initials E 500. Since it has long been known and is widely used, the salt has many related

names such as baking soda, bread soda, cooking soda, and bicarbonate of soda. In colloquial usage, its name is

shortened to sodium bicarb, bicarb soda, or simply bicarb. The word saleratus, from Latin sal

æratus meaning aerated salt, was widely used in the 19th century for both sodium bicarbonate and potassium

bicarbonate. The term has now fallen out of common usage.

Contents

  [hide] 

1 History

2 Production

3 Mining

4 Chemistry

o 4.1 Thermal decomposition

5 Applications

o 5.1 Fire extinguisher

o 5.2 Cooking

o 5.3 Neutralization of acids and bases

o 5.4 Medical uses

o 5.5 Personal hygiene

o 5.6 Baking soda in sports

o 5.7 As a cleaning agent

o 5.8 As a biopesticide

o 5.9 Cattle feed supplement

o 5.10 Miscellaneous

6 In popular culture

o 6.1 Film

7 See also

8 References

9 Further reading

10 External links

History[edit source | editbeta]

The ancient Egyptians used natural deposits of natron, a mixture consisting mostly of sodium carbonate decahydrate,

and sodium bicarbonate. The natron was used as a cleansing agent like soap.

In 1791, a French chemist, Nicolas Leblanc, produced sodium carbonate, also known as soda ash. In 1846, two New

York bakers, John Dwight and Austin Church, established the first factory to develop baking soda from sodium

carbonate and carbon dioxide.[6]

This compound, referred to as saleratus, is mentioned in the famous novel Captains Courageous by Rudyard

Kipling as being used extensively in the 1800s in commercial fishing to prevent freshly-caught fish from spoiling.[7]

Production[edit source | editbeta]

Main article: Solvay process

NaHCO3 is mainly prepared by the Solvay process, which is the reaction of sodium chloride, ammonia, and carbon

dioxide in water. Calcium carbonate is used as the source of CO2 and the resultant calcium oxide is used to recover

the ammonia from the ammonium chloride. The product shows a low purity (75 %). Pure product is obtained from

sodium carbonate, water and carbon dioxide as reported in one of the following reactions. It is produced on the scale

of about 100,000 tonnes/year (as of 2001).[8]

NaHCO3 may be obtained by the reaction of carbon dioxide with an aqueous solution of sodium hydroxide. The initial

reaction produces sodium carbonate:

CO2 + 2 NaOH → Na2CO3 + H2O

Further addition of carbon dioxide produces sodium bicarbonate, which at

sufficiently high concentration will precipitate out of solution:

Na2CO3 + CO2 + H2O → 2 NaHCO3

Commercial quantities of baking soda are also produced by a similar

method: soda ash, mined in the form of the ore trona, is dissolved in water

and treated with carbon dioxide. Sodium bicarbonate precipitates as a

solid from this method:

Na2CO3 + CO2 + H2O → 2 NaHCO3

Mining[edit source | editbeta]

Naturally occurring deposits of nahcolite (NaHCO3) are found in

the Eocene-age (55.8–33.9 Ma) Green River Formation, Piceance

Basin in Colorado. Nahcolite was deposited as beds during periods of

high evaporation in the basin. It is commercially mined using in-situ

leach techniques involving dissolution of the nahcolite by heated

water that is pumped through the nahcolite beds and reconstituted

through a natural cooling crystallization process.

Chemistry[edit source | editbeta]

Sodium bicarbonate is an amphoteric compound. Aqueous solutions

are mildly alkaline due to the formation of carbonic

acid and hydroxide ion:

HCO−

3 + H2O → H

2CO

3 + OH−

Sodium bicarbonate can be used as a wash to remove any

acidic impurities from a "crude" liquid, producing a purer sample.

Reaction of sodium bicarbonate and anacid produce a salt and

carbonic acid, which readily decomposes to carbon dioxide and

water:

NaHCO3 + HCl → NaCl + H2CO3

H2CO3 → H2O + CO2(g)

Sodium bicarbonate reacts with acetic acid (found

in vinegar), producing sodium acetate, water,

and carbon dioxide:

NaHCO3 + CH3COOH → CH3COONa + H2O + CO2(g)

Sodium bicarbonate reacts with bases such

as sodium hydroxide to form carbonates:

NaHCO3 + NaOH → Na2CO3 + H2O

Sodium bicarbonate reacts with carboxyl

groups in proteins to give a

brisk effervescence from the formation of CO

2. This reaction is used to test for the

presence of carboxylic groups in protein.[citation

needed]

Thermal decomposition[edit

source | editbeta]

Above 50 °C, sodium bicarbonate gradually

decomposes into sodium carbonate, water

and carbon dioxide. The conversion is fast at

200 °C:[9]

2 NaHCO3 → Na2CO3 + H2O + CO2

Most bicarbonates undergo

this dehydration reaction. Further

heating converts the carbonate into

the oxide (at over 850°C):[9]

Na2CO3 → Na2O + CO2

These conversions are relevant to

the use of NaHCO3 as a fire-

suppression agent ("BC powder") in

some dry powder fire extinguishers.

Applications[edit

source | editbeta]

Fire extinguisher[edit

source | editbeta]

Sodium bicarbonate is used along

with sulphuric acid in some fire

extinguishers since the two react to

form carbon dioxide, an

extinguishing agent.

Cooking[edit

source | editbeta]

Main article: Leavening agent

Sodium bicarbonate, referred to as

"baking soda" is primarily used in

cooking (baking), as a leavening

agent. It reacts with acidic

components in batters, releasing

carbon dioxide, which causes

expansion of the batter and forms

the characteristic texture and grain

in pancakes, cakes, quick breads,

soda bread, and other baked and

fried foods. Acidic compounds that

induce this reaction

include phosphates, cream of

tartar, lemon

juice, yogurt, buttermilk, cocoa, vine

gar, etc. Sodium bicarbonate can

be substituted for baking

powder provided sufficient acid

reagent is also added to the recipe.

[10] Many forms of baking powder

contain sodium bicarbonate

combined with calcium acid

phosphate, sodium aluminum

sulphate [11] or cream of tartar.

Sodium bicarbonate was

sometimes used in cooking

vegetables, to make them softer,

although this has gone out of

fashion, as most people now prefer

firmer vegetables. However, it is still

used in Asian cuisine to tenderise

meats. Baking soda may react with

acids in food, including Vitamin

C (L-ascorbic acid). It is also used

in breadings such as for fried foods

to enhance crispness.

Heat causes sodium bicarbonate to

act as a raising agent by releasing

carbon dioxide when used in

baking. The carbon dioxide

production starts at temperatures

above 80 °C. Since the reaction

does not occur at room

temperature, mixtures (cake batter,

etc.) can be allowed to stand

without rising until they are heated

in the oven.

Neutralization of acids

and bases[edit

source | editbeta]

Many laboratories keep a bottle of

sodium bicarbonate powder within

easy reach, because sodium

bicarbonate is amphoteric, reacting

with acids and bases. Furthermore,

as it is relatively innocuous in most

situations, there is no harm in using

excess sodium bicarbonate. Also,

sodium bicarbonate powder may be

used to smother a small fire, as

heating of sodium bicarbonate

releases carbon dioxide.[12]

A wide variety of applications

follows from its neutralization

properties, including reducing the

spread of white phosphorus from

incendiary bullets inside an afflicted

soldier's wounds.[13][medical citation needed]

Medical uses[edit

source | editbeta]

Sodium bicarbonate mixed with

water can be used as an antacid to

treat acid indigestion and heartburn.

[14] It is used as the medicinal

ingredient in gripe water for infants.

[15]

Sodium bicarbonate has been

known to be used in first aid, in

treating scalding, to prevent

blistering and scarring with

instructions to cover the scalded

area with a liberal layer of sodium

bicarbonate and water paste and

seek medical assistance. This is

due to the endothermic reaction

that occurs between sodium

bicarbonate and water and sodium

bicarbonate's mild antiseptic

properties[16][medical citation needed]

Intravenous sodium bicarbonate is

an aqueous solution that is

sometimes used for cases

of acidosis, or when there are

insufficient sodium or bicarbonate

ions in the blood.[17] In cases of

respiratory acidosis, the infused

bicarbonate ion drives the carbonic

acid/bicarbonate buffer of plasma to

the left and, thus, raises the pH. It is

for this reason that sodium

bicarbonate is used in medically

supervised cardiopulmonary

resuscitation. Infusion of

bicarbonate is indicated only when

the blood pH is markedly (<7.1–7.0)

low.[18]

Oral sodium bicarbonate has been

shown to slow progression to end

stage renal disease in individuals

with stage 4 chronic kidney

disease and metabolic

acidosis (plasma sodium

bicarbonate levels 16-20meq/L). [19]

It is used as well for treatment

of hyperkalemia. Since sodium

bicarbonate can cause alkalosis, it

is sometimes used to treat aspirin

overdoses. Aspirin requires an

acidic environment for proper

absorption, and the basic

environment diminishes aspirin

absorption in the case of an

overdose. Sodium bicarbonate has

also been used in the treatment

of tricyclic antidepressant overdose.

[20] It can also be applied topically as

a paste, with three parts baking

soda to one part water, to relieve

some kinds of insect bites and

stings (as well as accompanying

swelling).[21]

Adverse reactions to the

administration of sodium

bicarbonate can include metabolic

alkalosis, edema due to sodium

overload, congestive heart

failure, hyperosmolar syndrome,

hypervolemic hypernatremia,

and hypertension due to increased

sodium. In patients consuming a

high-calcium or dairy-rich

diet, calcium supplements, or

calcium-containing antacids such

as calcium carbonate (e.g., Tums),

the use of sodium bicarbonate can

cause milk-alkali syndrome, which

can result in metastatic

calcification, kidney stones, and

kidney failure.

Sodium bicarbonate can be used to

treat an allergic reaction to plants

such as poison -ivy -oak or -

sumac to relieve some of the

associated itching.[22]

Bicarbonate of soda can also be

useful in removing splinters from

the skin.[23]

Personal hygiene[edit

source | editbeta]

Toothpaste containing sodium

bicarbonate has in several studies

shown to have a better whitening[24]

[24][25][26] and plaque removal effect[27]

[28] than toothpastes without it.

Sodium bicarbonate is also used as

an ingredient in some

mouthwashes. It works as a

mechanical cleanser on the teeth

and gums, neutralizes the

production of acid in the mouth and

also acts as anantiseptic to help

prevent infections.[citation needed]

Sodium bicarbonate in combination

with other ingredients can be used

to make a dry or wet deodorant.[29]

[30] It may also be used as a

shampoo.[31]

Sodium bicarbonate may be used

as a buffering agent, combined with

table salt, when creating a solution

for nasal irrigation.[32]

Baking soda in

sports[edit

source | editbeta]

Small amounts of sodium

bicarbonate have been shown to be

useful as a supplement for athletes

in speed-based events, like middle

distance running, lasting from about

one to seven minutes.[33][34] But

overdose is a serious risk because

sodium bicarbonate is slightly

toxic[35] and in particular

gastrointestinal irritation is of

concern.[34] Additionally this practice

causes a significant increase in

dietary sodium.

As a cleaning agent[edit

source | editbeta]

A paste from baking soda can be

very effective when used in

cleaning and scrubbing.[36] For

cleaning aluminium objects, the use

of sodium bicarbonate is

discouraged as it attacks the thin

unreactive protective oxide layer of

this otherwise very reactive metal.

A solution in warm water will

remove the tarnish from silver when

the silver is in contact with a piece

of aluminium foil [37] [38]  A paste of

sodium bicarbonate and water is

useful in removing surface rust as

the rust forms a water soluble

compound when in a concentrated

alkaline solution.[39] Cold water

should be used as hot water

solutions can corrode steel.[40]

Baking soda is commonly added to

washing machines as a

replacement for softener and to

remove odors from clothes. Sodium

bicarbonate is also effective in

removing heavy tea and coffee

stains from cups when diluted with

warm water.

During the Manhattan Project to

develop the atomic bomb in the

early 1940s, many scientists

investigated the toxic properties of

uranium. They found that uranium

oxides stick very well to cotton

cloth, but did not wash out with

soap or laundry detergent. The

uranium would wash out with a 2%

solution of sodium bicarbonate

(baking soda). Clothing can

become contaminated with

depleted uranium (DU) dust and

normal laundering will not remove

it. Those at risk of DU dust

exposure should have their clothing

washed with baking soda (about 6

ounces (170g) of baking soda in 2

gallons (7.5l) of water).[41]

As a biopesticide[edit

source | editbeta]

Sodium bicarbonate can be an

effective way of controlling fungus

growth,[42] and in the United States

is registered by the Environmental

Protection Agency as

a biopesticide.[43]

Cattle feed

supplement[edit

source | editbeta]

Sodium bicarbonate is sold as a

cattle feed supplement, in particular

as a buffering agent for the rumen.

[44]

Miscellaneous[edit

source | editbeta]

Sodium bicarbonate can be used to

extinguish small grease or electrical

fires by being thrown over the fire.

[12] However, it should not be

applied to fires in deep fryers, as it

may cause the grease to splatter.

[12]Sodium bicarbonate is used in

BC dry chemical fire

extinguishers as an alternative to

the more corrosive ammonium

phosphate in ABC extinguishers.

The alkali nature of sodium

bicarbonate makes it the only dry

chemical agent, besides Purple-K,

that was used in large-scale fire

suppression systems installed in

commercial kitchens. Because it

can act as an alkali, the agent has a

mild saponification effect on hot

grease, which forms a smothering

soapy foam. Dry chemicals have

since fallen out of favor for kitchen

fires, as they have no cooling effect

compared to the extremely effective

wet chemical agents specifically

designed for such hazards.[citation

needed]

Sodium bicarbonate is used in a

process for removing paint and

corrosion called sodablasting; the

process is particularly suitable for

cleaning aluminium panels which

can be distorted by other types of

abrasive. It can be administered to

pools, spas, and garden ponds to

raise pH levels.[45] It has

weak disinfectant properties,[46][47] an

d it may be an

effective fungicide against some

organisms.[48]

Since it acts as a neutralizing

agent, it can be used to absorb

odors that are caused by strong

acids.[citation needed] Because baking

soda will absorb musty smells, it

has become a reliable method for

used-book sellers when making

books less malodorous.[49]

Sodium bicarbonate is also used as

required to increase Total Alkinity

level in swimming pools and

aquarium freshwater fish tanks.

Some alternative practitioners have

promoted baking soda as

a cancer cure, which the American

Cancer Society has warned against

due to both its unproven

effectiveness and potential danger

in use. [50]

In popular culture[edit

source | editbeta]

Film[edit source | editbeta]

Sodium bicarbonate, as

'bicarbonate of soda', was a

frequent source of punch lines

for Groucho Marx in Marx

brothers movies. In Duck Soup,

Marx plays the leader of a nation at

war. In one scene, he receives a

message from the battlefield that

his general is reporting a gas

attack, and Groucho tells his aide,

"Tell him to take a teaspoonful of

bicarbonate of soda and a half a

glass of water."[51] In A Night at the

Opera, Groucho's character

addresses the opening night crowd

at an opera by saying of the lead

tenor, "Signor Lassparri comes from

a very famous family. His mother

was a well-known bass singer. His

father was the first man to stuff

spaghetti with bicarbonate of soda,

thus causing and curing indigestion

at the same time."[52]

See also[edit

source | editbeta]

Carbonic acid

Baking powder

List of minerals

Nahcolite

Natron

Natrona (disambiguation)

Trona

References[edit

source | editbeta]

1. ̂  "Physical Constants of

Inorganic

Compounds". CRC

Handbook, p. 4-85.

2. ^ a b "Aqueous solubility of

inorganic compounds at

various

temperatures". CRC

Handbook, p. 8-116.

3. ^ a b "Sodium Bicarbonate".

UNEP Publications.

4. ^ a b Goldberg, Robert N.;

Kishore, Nand; Lennen,

Rebecca M.

"Thermodynamic quantities

for the ionization reactions

of buffers in water". CRC

Handbook. pp. 7–13.

5. ^ a b Zumdahl, Steven S.

(2009). Chemical Principles

6th Ed. Houghton Mifflin

Company. p. A23. ISBN 0-

618-94690-X.

6. ̂  "Company History".

Church & Dwight Co.

7. ̂  Rudyard Kipling. Captains

Courageous. p. 25

8. ̂  Holleman, A. F.; Wiberg,

E. "Inorganic Chemistry"

Academic Press: San

Diego, 2001. ISBN 0-12-

352651-5.

9. ^ a b "Decomposition of

Carbonates". General

Chemistry Online.

10. ̂  Radiation Cookery Book

45th Edition, Radiation

Group Sales Ltd 1954

11. ̂  "Glossary Ingredients".

Cooking.com.

12. ^ a b c "Arm & Hammer

Baking Soda – Basics –

The Magic Of Arm &

Hammer Baking Soda".

Armhammer.com.

Retrieved 2009-07-30.

13. ̂  "White Phosphorus".

GlobalSecurity.org.

Retrieved 2007-09-26.

14. ̂  "Sodium Bicarbonate".

Jackson Siegelbaum

Gastroenterology. 1998.

15. ̂  List of ingredients – Life

Brand Gripe Water

16. ̂  "New Scientist Last Word

Blog: Soda soother". New

Scientist. Retrieved 22

September 2011.

17. ̂  "Sodium Bicarbonate

Intravenous

Infusion". Consumer

Medicine Information.

Better Health Channel.

2004-07-13.

18. ̂  "Respiratory Acidosis:

Treatment & Medication".

emedicine.

19. ̂  de Brito-Ashurst I,

Varagunam M, Raftery MJ,

Yaqoob MM. (Sep 2009).

"Bicarbonate

supplementation slows

progression of CKD and

improves nutritional

status.". J Am Soc

Nephrol. 20 (9): 2075–

84.PMID 19608703.

20. ̂  Knudsen, K;

Abrahamsson, J (Apr

1997). "Epinephrine and

sodium bicarbonate

independently and

additively increase survival

in experimental amitriptyline

poisoning". Critical Care

Medicine 25 (4): 669–

74. doi:10.1097/00003246-

199704000-00019. ISSN 00

90-3493. PMID 9142034.

21. ̂  "Insect bites and stings:

First aid". Mayo Clinic.

2008-01-15.

22. ̂  What is Sodium

Bicarbonate Used For?.

Virtuowl.com. Retrieved on

2010-09-24.

23. ̂  [1]

24. ^ a b Kleber, CJ; Moore, MH,

Nelson, BJ (1998).

"Laboratory assessment of

tooth whitening by sodium

bicarbonate

dentifrices.". The Journal of

clinical dentistry 9 (3): 72–

5. PMID 10518866.

25. ̂  Koertge, TE; Brooks, CN,

Sarbin, AG, Powers, D,

Gunsolley, JC (1998). "A

longitudinal comparison of

tooth whitening resulting

from dentifrice use.". The

Journal of clinical

dentistry 9 (3): 67–

71. PMID 10518865.

26. ̂  Yankell, SL; Emling, RC,

Petrone, ME, Rustogi, K,

Volpe, AR, DeVizio, W,

Chaknis, P, Proskin, HM

(1999). "A six-week clinical

efficacy study of four

commercially available

dentifrices for the removal

of extrinsic tooth

stain.". The Journal of

clinical dentistry 10 (3 Spec

No): 115–

8.PMID 10825858.

27. ̂  Mankodi, S; Berkowitz, H,

Durbin, K, Nelson, B

(1998). "Evaluation of the

effects of brushing on the

removal of dental

plaque.". The Journal of

clinical dentistry 9 (3): 57–

60. PMID 10518862.

28. ̂  Putt, MS; Milleman, KR,

Ghassemi, A, Vorwerk, LM,

Hooper, WJ, Soparkar, PM,

Winston, AE, Proskin, HM

(2008). "Enhancement of

plaque removal efficacy by

tooth brushing with baking

soda dentifrices: results of

five clinical studies.". The

Journal of clinical

dentistry 19 (4): 111–

9. PMID 19278079.

29. ̂  Lamb, John Henderson

(31 May 1946). "Sodium

Bicarbonate: An Excellent

Deodorant". The Journal of

Investigative

Dermatology 7 (3): 131–

133. doi:10.1038/jid.1946.1

3.

30. ̂  "Bicarb soda: natural

body deodorant". Retrieved

5 May 2012.

31. ̂  Bouchard, Mallory (2010-

05-04). "A Green and

Healthy Beauty Secret:

Going Shampoo-

Free". Four Green Steps.

32. ̂  Ralph B. Metson,

M.D., The Harvard Medical

School Guide to Healing

Your Sinues (McGraw Hill

2005), at p. 68.

33. ̂  Bee, Peta (2008-08-

16). "Is bicarbonate of soda

a performance enhancing

drug". The Times (London).

Retrieved 2010-05-23.

34. ^ a b Ergogenic Aids. U.

Retrieved on 2011-09-11.

35. ̂  Baking soda overdose –

All Information. Umm.edu

(2009-10-19). Retrieved on

2010-09-24.

36. ̂  "Arm & Hammer Baking

Soda – Basics – The Magic

Of Arm & Hammer Baking

Soda". Armhammer.com.

Retrieved 2009-07-30.

37. ̂  Eco Silver Polishing.

instructables.com (2006-12-

20). Retrieved on 2011-10-

07.

38. ̂  "Put a Shine on It".

scifun.chem.wisc.edu.

Retrieved 2011-03-06.

39. ̂  Catherine E. Housecroft;

Alan G. Sharpe (2008).

"Chapter 22: d-block metal

chemistry: the first row

elements". Inorganic

Chemistry, 3rd Edition.

Pearson. p. 716. ISBN 978-

0-13-175553-6.

40. ̂  .http://

www.sciencelab.com/

msds.php?

msdsId=9927263

41. ̂  Orcutt,

JA. "Scientist". Pharmacolo

gy and Toxicology of

Uranium Compounds.

McGraw-Hill. Retrieved 21

March 2012.

42. ̂  Potassium bicarbonate

(073508) and Sodium

bicarbonate (073505) Fact

Sheet United States

Environmental Protection

Agency. Updated 17

February 2011. Retrieved

25 November 2011.

43. ̂  Registered Biopesticides

04/29/02 United States

Environmental Protection

Agency. Updated 29 March

2002. Retrieved 25

November 2011.

44. ̂  "Acidosis Health Warning

for Livestock Farmers".

Retrieved 5 May 2012.

45. ̂  "Arm & Hammer Baking

Soda – Basics – The Magic

Of Arm & Hammer Baking

Soda". Armhammer.com.

Retrieved 2009-07-30.

46. ̂  Malik, Ys; Goyal, Sm

(May 2006). "Virucidal

efficacy of sodium

bicarbonate on a food

contact surface against

feline calicivirus, a

norovirus

surrogate". International

Journal of Food

Microbiology 109 (1–2):

160–3. do

i:10.1016/j.ijfoodmicro.2005

.08.033. ISSN 0168-1605. 

PMID 16540196.

47. ̂  William A. Rutala, Susan

L. Barbee, Newman C.

Aguiar, Mark D. Sobsey,

David J. Weber, (2000).

"Antimicrobial Activity of

Home Disinfectants and

Natural Products Against

Potential Human

Pathogens".Infection

Control and Hospital

Epidemiology (The

University of Chicago Press

on behalf of The Society for

Healthcare Epidemiology of

America)21 (1): 33–

38. doi:10.1086/501694. P

MID 10656352.

48. ̂  Zamani, M; Sharifi,

Tehrani, A; Ali, Abadi, Aa

(2007). "Evaluation of

antifungal activity of

carbonate and bicarbonate

salts alone or in

combination with biocontrol

agents in control of citrus

green

mold".Communications in

agricultural and applied

biological sciences 72 (4):

773–7. PMID 18396809.

49. ̂  Gail Altman (2006-05-

22). "Book Repair for

BookThinkers: How To

Remove Odors From

Books". The

BookThinker (69).

50. ̂  "Sodium Bicarbonate".

51. ̂  http://www.imdb.com/

title/tt0023969/trivia?tab=qt

52. ̂  http://www.imdb.com/

title/tt0026778/trivia?

tab=qt&ref_=tt_trv_qu

Further reading[edit

source | editbeta]

Bishop, D; Edge, J; Davis, C;

Goodman, C (May 2004).

"Induced metabolic alkalosis

affects muscle metabolism and

repeated-sprint

ability". Medicine and science

in sports and exercise 36 (5):

807–

13

.doi:10.1249/01.MSS.0000126

392.20025.17. ISSN 0195-

9131. PMID 15126714.

David R. Lide, ed. (2003). CRC

Handbook of Chemistry and

Physics (84th ed.). Boca

Raton, FL: CRC

Press. ISBN 0-8493-0484-9.

External links[edit

source | editbeta]

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media related to: Sodium

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recipe/module on

Baking soda

International Chemical Safety

Card 1044

Differences between Baking

Soda and Baking Powder

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Sodium hydroxideFrom Wikipedia, the free encyclopedia

Sodium hydroxide

Preferred IUPAC name [hide]

Sodium hydroxide[1]

Systematic name [hide]

Sodium oxidanide[citation needed]

Other names[hide]

Caustic soda

Lye [2][3]

Ascarite

White caustic

Sodium hydrate[1]

Identifiers

CAS number 1310-73-2

PubChem 14798

ChemSpider 14114

UNII 55X04QC32I

EC number 215-185-5

UN number 1823

KEGG D01169

MeSH Sodium+Hydroxide

ChEBI CHEBI:32145

RTECS number WB4900000

Gmelin Reference 68430

Jmol-3D images Image 1

SMILES

[show]

InChI

[show]

Properties

Molecular formula NaOH

Molar mass 39.9971 g mol-1

Appearance White, waxy, opaque crystals

Odor odorless

Density 2.13 g/cm3

Melting point318 °C, 591 K, 604 °F

Boiling point1388 °C, 1661 K, 2530 °F

Solubility in water 111 g/100 mL (at 20 °C)

Solubility inmethanol 23.8 g/100 mL

Solubility in ethanol <<13.9 g/100 mL

Vapor pressure <2.4 kPa (at 20 °C)

Acidity (pKa) 13

Refractive index(nD) 1.3576

Hazards

MSDS External MSDS

GHS pictograms

EU Index 011-002-00-6

EU classification

C

R-phrases R35

S-phrases (S1/2), S26, S37/39, S45

NFPA 704

0

3

1

ALK

Related compounds

Other anions Sodium hydrosulfide

Other cations Caesium hydroxide

Lithium hydroxide

Potassium hydroxide

Rubidium hydroxide

(verify) (what is: / ?)

Except where noted otherwise, data are given for materials in

their standard state (at 25 °C, 100 kPa)

Infobox references

Sodium hydroxide, also known as caustic soda,[2][3] or lye, is an inorganic compound with the chemical

formula NaOH (also written as NaHO). It is a white solid, and is a highly caustic metallic base and alkali salt. It is

available in pellets, flakes, granules, and as a 50% saturated solution.[citation needed]

Sodium hydroxide is soluble in water, ethanol and methanol. This alkali is deliquescent and readily

absorbs moisture and carbon dioxide in air.

Sodium hydroxide is used in many industries, mostly as a strong chemical base in the manufacture

of pulp and paper, textiles, drinking water, soaps and detergentsand as a drain cleaner. Worldwide production in

2004 was approximately 60 million tonnes, while demand was 51 million tonnes.[4]

Contents

  [hide] 

1   Properties

o 1.1   Physical properties

o 1.2   Chemical properties

1.2.1   Reaction with acids

1.2.2   Reaction with acidic oxides

1.2.3   Reaction with amphoteric metals and oxides

1.2.4   Precipitant

1.2.5   Saponification

2   Production

3   Uses

o 3.1   Chemical pulping

o 3.2   Tissue digestion

o 3.3   Dissolving amphoteric metals and compounds

o 3.4   Esterification and transesterification reagent

o 3.5   Food preparation

o 3.6   Cleaning agent

o 3.7   Historical uses

o 3.8   Experimental

4   Safety

5   See also

6   References

7   Bibliography

8   External links

Properties[edit source | edit beta ]

Physical properties[edit source | edit beta ]

Pure sodium hydroxide is a whitish solid, sold in pellets, flakes, and granular form, as well as in solution. It is highly

soluble in water, with a lower solubility in ethanol and methanol, but is insoluble in ether and other non-polar solvents.

Similar to the hydration of sulfuric acid, dissolution of solid sodium hydroxide in water is a highly exothermic reaction

in which a large amount of heat is liberated, posing a threat to safety through the possibility of splashing. The

resulting solution is usually colourless and odorless with slippery feeling upon contact in common with other alkalis.

Chemical properties[edit source | edit beta ]

Reaction with acids[edit source | edit beta ]

Sodium hydroxide reacts with protic acids to produce water and the corresponding salts. For example, when sodium

hydroxide reacts with hydrochloric acid, sodium chloride is formed:

NaOH(aq) + HCl(aq) → NaCl(aq) + H2O(l)

In general, such neutralization reactions are represented by one simple net ionic equation:

OH − (aq) + H + (aq) → H2O(l)

This type of reaction with a strong acid releases heat, and hence is exothermic. Such acid-base

reactions can also be used for titrations. However, sodium hydroxide is not used as a primary

standard because it is hygroscopic and absorbs carbon dioxide from air.

Reaction with acidic oxides[edit source | edit beta ]

Sodium hydroxide also reacts with acidic oxides, such as sulfur dioxide. Such reactions are often used to

"scrub" harmful acidic gases (like SO2 and H2S) produced in the burning of coal and thus prevent their

release into the atmosphere. For example,

2 NaOH + CO2 → Na2CO3 + H2O

Reaction with amphoteric metals and oxides[edit source | edit beta ]

Sodium hydroxide slowly reacts with glass to form sodium silicate. Because of this, glass joints

and stopcocks exposed to sodium hydroxide have a tendency to "freeze". Flasks and glass-

lined chemical reactors are damaged by long exposure to hot sodium hydroxide, which also frosts the

glass. Sodium hydroxide does not attack iron since iron does not have amphoteric properties (i.e., it

only dissolves in acid, not base). A few transition metals, however, may react vigorously with sodium

hydroxide.

In 1986, an aluminium road tanker in the UK was mistakenly used to transport 25% sodium hydroxide

solution,[5] causing pressurization of the contents and damage to the tanker. The pressurization was

due to the hydrogen gas which is produced in the reaction between sodium hydroxide and aluminium:

2 Al + 2 NaOH + 6 H2O → 2 Na[Al(OH)4] + 3 H2

Precipitant[edit source | edit beta ]

Unlike sodium hydroxide, the hydroxides of most transition metals are insoluble, and therefore

sodium hydroxide can be used to precipitate transition metal hydroxides. The following colours are

observed: Blue-copper, Green-Iron(II), Yellow/Brown-Iron(III). Zinc and Lead salts dissolve in

excess sodium hydroxide to give a clear solution of Na2ZnO2 or Na2PbO2.

Aluminium hydroxide is used as a gelatinous flocculant to filter out particulate matter in water

treatment. Aluminium hydroxide is prepared at the treatment plant fromaluminium sulfate by

reacting it with sodium hydroxide.

Al2(SO4)3 + 6 NaOH → 2 Al(OH)3 + 3 Na2SO4

Saponification[edit source | edit beta ]

Sodium hydroxide can be used for the base-driven hydrolysis of esters (as

in saponification), amides and alkyl halides. However, the limited solubility of sodium

hydroxide in organic solvents means that the more soluble potassium hydroxide (KOH) is

often preferred.

Production[edit source | edit beta ]

Sodium hydroxide is industrially produced as a 50% solution by variations of the

electrolytic chloralkali process. Chlorine gas is also produced in this process. Solid sodium

hydroxide is obtained from this solution by the evaporation of water. Solid sodium hydroxide

is most commonly sold as flakes, prills, and cast blocks.[4]

In 2004, world production was estimated at 60 million dry metric tonnes of sodium hydroxide,

and demand was estimated at 51 million tonnes.[4] In 1998, total world production was around

45 million tonnes. North America and Asia collectively contributed around 14 million tonnes,

while Europe produced around 10 million tonnes. In the United States, the major producer of

sodium hydroxide is the Dow Chemical Company, which has annual production around

3.7 million tonnes from sites at Freeport, Texas, and Plaquemine, Louisiana. Other major US

producers include OxyChem, PPG, Olin, Pioneer Companies, Inc. (PIONA, which was

purchased by Olin), and Formosa. All of these companies use the chloralkali process.[6]

Historically sodium hydroxide is produced by treating sodium carbonate with calcium

hydroxide in a metathesis reaction. (Sodium hydroxide is soluble while calcium carbonate is

not.) This process was called causticizing.[7]

Ca(OH)2(aq) + Na2CO3(s) → CaCO3↓ + 2 NaOH(aq)

This process was superseded by the Solvay process in the late 19th century, which was

in turn supplanted by the chloralkali process which we use today.

Sodium hydroxide is also produced by combining pure sodium metal with water. The

byproducts are hydrogen gas and heat, often resulting in a flame, making this a common

demonstration of the reactivity of alkali metals in academic environments; however, it is

not commercially viable, as the isolation of sodium metal is typically performed by

reduction or electrolysis of sodium compounds including sodium hydroxide.

Uses[edit source | edit beta ]

Canister of sodium hydroxide.

Sodium hydroxide is the principal strong base used in the chemical industry. In bulk it is

most often handled as an aqueous solution, since solutions are cheaper and easier to

handle. Sodium hydroxide, a strong base, is responsible for most of these applications.

Another strong base such as potassium hydroxide is likely to yield positive results as

well.

Overall 56% of sodium hydroxide produced is used by the chemical industry, with 25%

of the same total used by the paper industry. Sodium hydroxide is also used for the

manufacture of sodium salts and detergents, for pH regulation, and for organic

synthesis. It is used in the Bayer process of aluminium production.[4]

Sodium hydroxide is used in many scenarios where it is desirable to increase the

alkalinity of a mixture, or to neutralize acids.

For example, sodium hydroxide is used as an additive in drilling mud to

increase alkalinity in bentonite mud systems, to increase the mud viscosity, and to

neutralise anyacid gas (such as hydrogen sulfide and carbon dioxide) which may be

encountered in the geological formation as drilling progresses.

In the same industry, poor quality crude oil can be treated with sodium hydroxide to

remove sulfurous impurities in a process known as caustic washing. As above, sodium

hydroxide reacts with weak acids such as hydrogen sulfide and mercaptans to give the

non-volatile sodium salts which can be removed. The waste which is formed is toxic and

difficult to deal with, and the process is banned in many countries because of this. In

2006, Trafigura used the process and then dumped the waste in Africa.[8][9]

See also: hydrodesulfurization

Chemical pulping[edit source | edit beta ]

Main article: Pulp (paper)

Sodium hydroxide is also widely used in pulping of wood for making paper or

regenerated fibers. Along with sodium sulfide, sodium hydroxide is a key component of

the white liquor solution used to separatelignin from cellulose fibers in the kraft process.

It also plays a key role in several later stages of the process of bleaching the brown

pulp resulting from the pulping process. These stages

include oxygendelignification, oxidative extraction, and simple extraction, all of which

require a strong alkaline environment with a pH > 10.5 at the end of the stages.

Tissue digestion[edit source | edit beta ]

In a similar fashion, sodium hydroxide is used to digest tissues, such as in a process

that was used with farm animals at one time. This process involved placing a carcass

into a sealed chamber, then adding a mixture of sodium hydroxide and water (which

breaks the chemical bonds that keep the flesh intact). This eventually turns the body into

a liquid with coffee-like appearance,[10][11] and the only solid that remains are bone hulls,

which could be crushed between one's fingertips.[12] Sodium hydroxide is frequently used

in the process of decomposing roadkill dumped in landfills by animal disposal

contractors.[11] Due to its low cost and availability, it has been used to dispose of corpses

by criminals. In Mexico, a man who worked for different drug cartels admitted disposing

over 300 bodies with it.[13]

Dissolving amphoteric metals and compounds[edit

source | edit beta ]

Strong bases attack aluminium. Sodium hydroxide reacts with aluminium and water to

release hydrogen gas. The aluminium takes the oxygen atom from sodium hydroxide,

which in turn takes the oxygen atom from the water, and releases the two hydrogen

atoms, The reaction thus produces hydrogen gas and sodium aluminate. In this reaction,

sodium hydroxide acts as an agent to make the solution alkaline, which aluminium can

dissolve in. This reaction can be useful in etching, removing anodizing, or converting a

polished surface to a satin-like finish, but without further passivation such

as anodizing or alodining the surface may become degraded, either under normal use or

in severe atmospheric conditions.

In the Bayer process, sodium hydroxide is used in the refining of alumina containing

ores (bauxite) to produce alumina (aluminium oxide) which is the raw material used to

produce aluminium metal via theelectrolytic Hall-Héroult process. Since the alumina

is amphoteric, it dissolves in the sodium hydroxide, leaving impurities less soluble at

high pH such as iron oxides behind in the form of a highly alkaline red mud.

See also: Ajka alumina plant accident

Other amphoteric metals are zinc and lead which dissolve in concentrated sodium

hydroxide solutions to give sodium zincate and sodium plumbate respectively.

Esterification and transesterification reagent[edit

source | edit beta ]

Sodium hydroxide is traditionally used in soap making (cold

process soap, saponification).[14] It was made in the nineteenth century for a hard

surface rather than liquid product because it was easier to store and transport.

For the manufacture of biodiesel, sodium hydroxide is used as a catalyst for

the transesterification of methanol and triglycerides. This only works

with anhydrous sodium hydroxide, because combined with water the fat would turn

into soap, which would be tainted with methanol. It is used more often than potassium

hydroxide because it is cheaper and a smaller quantity is needed.

Food preparation[edit source | edit beta ]

Food uses of sodium hydroxide include washing or chemical peeling

of fruits and vegetables, chocolate and cocoa processing, caramel

coloring production, poultry scalding, soft drink processing, and thickening ice

cream. Olives are often soaked in sodium hydroxide for

softening; Pretzels and German lye rolls are glazed with a sodium hydroxide solution

before baking to make them crisp. Owing to the difficulty in obtaining food grade sodium

hydroxide in small quantities for home use, sodium carbonate is often used in place of

sodium hydroxide.[15]

Specific foods processed with sodium hydroxide include:

The Pinoy or Filipino dessert (kakanin) called kutsinta uses a bit of lye water to help

give the rice flour batter a jelly like consistency.

A similar process is also used in the kakanin known as pitsi-pitsi or pichi-pichi (pit-

chi-pit-chi) except that the mixture uses grated cassava instead of rice flour.

The Scandinavian delicacy known as lutefisk (from lutfisk, "lye fish").

Hominy  is dried maize (corn) kernels reconstituted by soaking in lye-water. These

expand considerably in size and may be further processed by frying to make corn

nuts or by drying and grinding to make grits.Nixtamal is similar, but uses calcium

hydroxide instead of sodium hydroxide.

Sodium hydroxide is also the chemical that causes gelling of egg whites in the

production of Century eggs.

German pretzels are poached in a boiling sodium carbonate solution or cold sodium

hydroxide solution before baking, which contributes to their unique crust.

Lye-water is an essential ingredient in the crust of the traditional baked Chinese

moon cakes.

Most yellow coloured Chinese noodles are made with lye-water but are commonly

mistaken for containing egg.

Some methods of preparing olives involve subjecting them to a lye-based brine.[16]

Cleaning agent[edit source | edit beta ]

Main article: Cleaning agent

Sodium hydroxide is frequently used as an industrial cleaning agent where it is often

called "caustic". It is added to water, heated, and then used to clean process equipment,

storage tanks, etc. It can dissolvegrease, oils, fats and protein based deposits. It is also

used for cleaning waste discharge pipes under sinks and drains in domestic

properties. Surfactants can be added to the sodium hydroxide solution in order to

stabilize dissolved substances and thus prevent redeposition. A sodium hydroxide soak

solution is used as a powerful degreaser on stainless steel and glass bakeware. It is

also a common ingredient in oven cleaners.

A common use of sodium hydroxide is in the production of parts washer detergents.

Parts washer detergents based on sodium hydroxide are some of the most aggressive

parts washer cleaning chemicals. The sodium hydroxide based detergent include

surfactants, rust inhibitors and defoamers. A parts washer heats water and the detergent

in a closed cabinet and then sprays the heated sodium hydroxide and hot water at

pressure against dirty parts for degreasing applications. Sodium hydroxide used in this

manner replaced many solvent based systems in the early 1990s[citation

needed] when trichloroethane was outlawed by the Montreal Protocol. Water and sodium

hydroxide detergent based parts washers are considered to be an environmental

improvement over the solvent based cleaning methods.

Hardware stores grade sodium hydroxide to be used as a type of drain cleaners.

Paint stripping with caustic soda

Sodium hydroxide is used in the home as a type of drain opener to unblock clogged

drains, usually in the form of a dry crystal or as a thick liquid gel. The alkali

dissolves greases to produce water soluble products. It

also hydrolyzes the proteins such as those found in hair which may block water pipes.

These reactions are sped by the heat generated when sodium hydroxide and the other

chemical components of the cleaner dissolve in water. Such alkaline drain cleaners and

their acidic versions are highly corrosive and should be handled with great caution.

Sodium hydroxide is used in some relaxers to straighten hair. However, because of the

high incidence and intensity of chemical burns, manufacturers of chemical relaxers use

other alkaline chemicals in preparations available to average consumers. Sodium

hydroxide relaxers are still available, but they are used mostly by professionals.

A solution of sodium hydroxide in water was traditionally used as the most common

paint stripper on wooden objects. Its use has become less common, because it can

damage the wood surface, raising the grain and staining the colour.

Historical uses[edit source | edit beta ]

Sodium hydroxide has been used for detection of carbon monoxide poisoning, with

blood samples of such patients turning to a vermilion color upon the addition of a few

drops of sodium hydroxide.[17] Today, carbon monoxide poisoning can be detected

by CO oximetry.

Experimental[edit source | edit beta ]

Sodium hydroxide is also being used experimentally in a new technology to create

synthetic gasoline.[18]

Sodium hydroxide test  for flavonoids

Safety[edit source | edit beta ]

Chemical burns caused by sodium hydroxide solution photographed 44 hours after exposure.

Like other corrosive acids and alkalis, drops of sodium hydroxide solutions can

decompose proteins and lipids in skin, eyes or other living tissues via amide

hydrolysisand ester hydrolysis which consequently causes chemical burns and may

induce permanent blindness if it contacts eyes.[2][3] Solid alkali may also express its

corrosive nature if there is water so protective equipment such as rubber gloves, safety

clothing and eye protection should always be used when handling the material or its

solutions.

Moreover, dissolution of sodium hydroxide is highly exothermic, and the resulting heat

may cause heat burns or ignite flammables. It also produces heat when reacted with

acids.

The standard first aid measures for alkali spills on the skin is, as for other corrosives,

irrigation with large quantities of water. Washing is continued for at least ten to fifteen

minutes.

Sodium hydroxide is corrosive to several metals, like aluminium which reacts with the

alkali to produce flammable hydrogen gas on contact:[19]

2 Al + 2 NaOH + 2 H2O → 3 H2 + 2 NaAlO2

2 Al + 6 NaOH + x H2O → 3 H2 + 2 Na3AlO3 + x H2O

2 Al + 2 NaOH + 6 H2O → 3 H2 + 2 NaAl(OH)4

Sodium hydroxide is also mildly corrosive to glass, which can cause

damage to glazing or freezing of ground glass joints. Careful storage is

needed.

See also[edit source | edit beta ]

HAZMAT Class 8 Corrosive Substances

Common chemicals

List of elemental cleaning agents

References[edit source | edit beta ]

1. ^ a b "Sodium Hydroxide - Compound Summary". Retrieved June 12,

2012.

2. ^ a b c "Material Safety Datasheet".

3. ^ a b c "Material Safety Datasheet 2".

4. ^ a b c d Cetin Kurt, Jürgen Bittner (2005), "Sodium

Hydroxide",Ullmann's Encyclopedia of Industrial Chemistry,

Weinheim: Wiley-VCH,doi:10.1002/14356007.a24_345.pub2

5. ̂  Stamell, Jim (2001), EXCEL HSC Chemistry, Pascal Press,

p. 199,ISBN 978-1-74125-299-6

6. ̂  Kirk-Othmer Encyclopedia of Chemical Technology 5th edition

(online, account needed), John Wiley & Sons. Accessed November

21, 2005.

7. ̂  Deming, Horace G. (1925). General Chemistry: An Elementary

Survey Emphasizing Industrial Applications of Fundamental

Principles (2nd ed.). New York: John Wiley & Sons, Inc. p. 452.

8. ̂  Sample, Ian (16 September 2009). "Trafigura case: toxic slop left

behind by caustic washing". The Guardian. Retrieved 2009-09-17.

9. ̂  "Trafigura knew of waste dangers". BBC Newsnight. 16

September 2009. Retrieved 2009-09-17.

10. ̂  Ayres, Chris (27 February 2010) Clean green finish that sends a

loved one down the drain Times Online. Retrieved 2013-02-20.

11. ^ a b Thacker, H. Leon; Kastner, Justin (August 2004). Carcass

Disposal: A Comprehensive Review. Chapter 6. National

Agricultural Biosecurity Center, Kansas State University, 2004.

Retrieved 2010-03-08

12. ̂  Roach, Mary (2004). Stiff: The Curious Lives of Human Cadavers,

New York: W.W. Norton & Company. ISBN 0-393-32482-6.

13. ̂  William Booth (January 27, 2009). "'Stewmaker' Stirs Horror in

Mexico". Washington Post.

14. ̂  Morfit, Campbell (1856). A treatise on chemistry applied to the

manufacture of soap and candles. Parry and McMillan.

15. ̂  "Hominy without Lye". National Center for Home Food

Preservation.

16. ̂  "Olives: Safe Methods for Home Pickling (application/pdf

Object)".ucanr.org. 2010 [last update]. Retrieved January 22, 2012.

17. ̂  Page 168 in: The Detection of poisons and strong drugs. Author:

Wilhelm Autenrieth. Publisher: P. Blakiston's son & Company, 1909.

18. ̂  Andrew Hough (18 October 2012). "British engineers produce

amazing 'petrol from air' technology". The Telegraph. Retrieved 21

October 2012.

19. ̂  "aluminium_water_hydrogen.pdf (application/pdf

Object)".www1.eere.energy.gov. 2008 [last update]. Retrieved

January 15, 2013.

Bibliography[edit source | edit beta ]

Euro Chlor-How is chlorine made? Chlorine Online

Greenwood, Norman N. ; Earnshaw, Alan (1997). Chemistry of the

Elements (2nd ed.). Butterworth–Heinemann. ISBN 0080379419.

Heaton, A. (1996) An Introduction to Industrial Chemistry, 3rd edition,

New York:Blackie. ISBN 0-7514-0272-9.

External links[edit source | edit beta ]

Wikimedia Commons has

media related to: Sodium

hydroxide

Look up sodium hydroxide in

Wiktionary, the free

dictionary.

International Chemical Safety Card 0360

NIOSH Pocket Guide to Chemical Hazards

CDC - Sodium Hydroxide - NIOSH Workplace Safety and Health

Topic

European Union Risk Assessment Report

Production by brine electrolysis

Titration of acids with sodium hydroxide; freeware for data analysis,

simulation of curves and pH calculation

Caustic soda production in continuous causticising plant by lime

soda process

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