ca u tell me the main things i should know abt in acids and bases??
ACIDS :
1. An
acid is a substance that will produce hydrogen ions (H
+) on dissolving in water.
There are two types of acids :
(i) Strong acid ---> Complete ionisation
(ii) Weak acid ---> Partial ionisation
Examples of strong acids are HCl and H
2SO
4 while all organic acids are weak acids.
Properties of acids :
1. An acid has a sour taste.
2. An acid will turn moist blue litmus paper red.
3. An acid will react with reactive metals to liberate hydrogen gas.
4. An acid will react with carbonates to liberate carbonates.
Tests for acids.
1. When moist blue litmus paper is brought into contact with an acid, there is a colour change from blue to red.
2.When solid sodium carbonate is brought into contact with the acid, there is effervescence and a gas carbon dioxide which turns lime water milky is liberated.
BASES :
1. An alkali or base is a substance that will produce hydroxide ions (OH
-) on dissolving in water.
Properties of alkalis :
1. An alkali has a soapy feel.
2. An alkali will turn moist red litmus paper blue.
3. An alkali will react with an acid to form a salt and water.
4. An alkali when heated with an ammonium salt will liberate ammonia gas.
Test for alkali :
1. When moist red litmus paper is placed into a alkali, there is a colour change from red to blue.
2. When an alkali is heated with ammonium chloride, a gas ammonia that turns red litmus paper blue is liberated.