Acid and Alkalis

Acids

Taste: Sour.
Touch: Like water.
Tested with litmus paper: Turn blue litmus red.
pH value: From 0 to less than 7.
Reaction with metals: Form hydrogen and a salt.
Reaction with carbonates: Form a salt, water and carbon dioxide.
Reaction with ammonium compounds: No reaction.

Alkalis

Taste: Bitter.
Touch: Soapy.
Tested with litmus paper: Turn red litmus blue.
pH value: From above 7 to 14.
Reaction with metals: No reaction.
Reaction with carbonates: No reaction.
Reaction with ammonium compounds: Give off ammonia gas.

Note: Strong acids and alkalis are corrosive and dangerous.