Sandeep ppt on acids, bases and salts for vii
Post on 15-Jul-2015
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Sour in taste
Produce H+(hydrogen ions)
Turns blue litmus red
Acids+ metals salt+ hydrogen gas conduct
electricity are corrosive(acid rain)
pH less then 7
Vinegar
Lemon juice
Orange juice
Curd
Tamarind
Amla
Black tea
Apple juice
Unripe mango
grapes
curd, lemon juice, orange juice and vinegar
taste sour. These substances taste sour
because they contain acids. The chemical
nature of such substances is acidic. The
word acid comes from the Latin word acere
which mean sour. The acids in these
substances are nature acids.
hydrochloric stomach acid
sulfuric acid car batteries
nitric acid explosives
acetic acid vinegar
carbonic acid sodas
phosphoric acid flavorings Common Acids
Formic acid ant’s sting
Citric acid lemons, oranges etc.
Lactic acid curd
Oxalic acid spinach
Ascorbic acid amla, citrus fruits
Tartaric acid tamarind, grapes, unripe
mangoes, etc.
Base bitter to taste
Soapy to touch
Water soluble base are called alkalis. All
alkalis are bases but all bases are not alkalis.
Turns red litmus blue
Ph greater then 7
Detergent
Baking soda
Drain cleaner
Antacid base
Ammonia sops(hand, dish)
Lime water
Milk of magnesia
baking soda taste sour? What is its taste?
Since, it does not taste sour it means, that it
has no acids in it. It is bitter in taste. If you
rub the solution between fingers, it feels
soapy on touching are know as base. The
nature of such substances is aid to be basic.
sodium hydroxide - soaps, drain cleaner
magnesium hydroxide - antacids
Aluminum hydroxide - antacid, deodorants
Calcium hydroxide - lime water
Ammonium hydroxide - window cleaners
Magnesium hydroxide - milk of magnesia
ammonium hydroxide - “ammonia” Common
base
Weak base :
potassium carbonate,
sodium carbonate
ammonia
Strong Bases:
sodium hydroxide;
sodium phosphate;
barium hydroxide;
calcium hydroxide
Litmus: A natural indicator
The most commonly used indicator is litmus.
It is extracted from lichens. It has a mauve
(purple) colour in distilled water. When
added to an acidic solution, it turns red and
when added to basic solution it turns blue. It
will be in the form of solution or in the form
of strips of paper, known as litmus paper.
Generally, it is available as red and blue
litmus paper.
Litmus (paper/solution)
Turmeric
China rose
Phenolphthalein (ph)
When an acidic solution is mixed with
a basic solution, both the solutions neutralise the effect of each other.
the reaction between an acid and a base is known as neutralisation. Salt and water are produced in this process with the evolution of heat.
Acid+ base salt+water (heat is evolved)
Hydrochloric acid (HCl)+sodium hydroxide (NaOH) sodium chloride (NaCl)+ water (H2O)
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