The Chemistry of Acids & Bases

The Chemistry of Acids & Bases

Properties of Acids• Dilute solution have a _____taste

• Aqueous solutions conduct an electric current What do we call substances that can conduct electric currents?

**The greater the # of ions in solution, the greater the electrical conductivity.

• Acids react with bases to form a water & salt _____________________

• Acids react with certain metals to produce H2 gas

Table J: _____________________________

• Acids cause acid-base indicators to change color

Lemons have citric acid!

Vinegar has acetic acid!

_________________

Strong acid =

Weak acid =

Properties of Bases

• Bases have a bitter taste.

• Bases have a slippery or soapy feeling.

• Bases conduct an electric current.

• Bases react with acids to form water & salt.

• Bases cause acid-based indicators to change color.

Strong base=

Weak base =

Arrhenius TheoryArrhenius Acid

= ______________________________________ ______________________________________

- Ex:

**Some notes on the hydrogen ion!: H+ is really just a _________! In a water solution, the positively charged proton

is attracted to an unshared pair of electrons in the

water molecules.

Proton ends up covalently bonding with water to form

_______________________

http://hogan.chem.lsu.edu/matter/chap26/animate3/an26_037.mov

So, acids dissolve in water & react to produce ______________ & ________________.

H2SO4 2H3O+ (aq) + SO4 2-

(aq)

H3SO4 3H3O+ (aq)

+ SO4 2- (aq)

Arrhenius TheoryArrhenius Base:

= _____________________________________________ _____________________________________________- Remember: hydroxide ion = OH-

NaOH Na+ (aq) + OH- (aq)

KOH K+ (aq) + OH- (aq)

http://hogan.chem.lsu.edu/matter/chap26/animate3/an26_038.mov

Other Acid/Base Definitions

Brønsted – Lowry Acids = _____________Brønsted – Lowry Bases = _____________

Note: A “proton” is really just a hydrogen atom that has lost it’s electron!

Lewis acid = _____________________________Lewis base = _____________________________

Neutralization Reactions= an Arrhenius acid reacts with an Arrhenius base to

produce water & a salt

- General reaction:

**All neutralization reactions have the same net equation:

=

http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/animations/HClandNaOHtgV8.html

Acid-Base Titration= the process of adding measured volumes of an acid or base

of known concentration to an acid or base of unknown concentration until neutralization takes place

- Through a titration, it is possible to calculate the concentration of the unknown solution:

MAVA = MBVB

http://www.chem.iastate.edu/group/Greenbowe/sections/projectfolder/flashfiles/stoichiometry/acid_base.html

Monoprotic Acid: H+ molarity = molarity of acid solution- Ex: 2.5M HCl = 2.5M H+

Diprotic Acid: H+ molarity = 2 x molarity of acid solution- Ex: 2.5M H2SO4 = ___ H+

Triprotic Acid: H+ molarity = 3 x molarity of acid solution- Ex: 2.5M H3SO4 = ___ H+

Monohydroxy Bases: OH- molarity = molarity of base solution- Ex: 3.0M NaOH = ___ OH-

Dihydroxy Bases: OH- molarity = 2 x molarity of base solution- Ex: 3.0M Ba(OH)2 = ___ OH-

Acidity vs. Alkalinity

** These terms refer to the relative strength of the acid or base in terms of H+ and OH- concentrations.**

- Acidity ___________________________- Alkalinity _________________________

[H+] > [OH-] :_________

[H+] < [OH-] :_________

pH Scale The pH scale expresses [H+] as a number from 0 to 14

Each pH unit represents a tenfold increase or decrease in [H+] and [OH-].

As [H+] increases, [OH-] decreases (and vice-versa).

Acid-Base Indicators

Indicator = ____________________________________

____________________________________

**REMEMBER: Everything you need to know about acid-base indicators is on Table M in the reference tables!!**

http://hogan.chem.lsu.edu/matter/chap27/demos/dm27_010.mov