Acids

  Acids solutions are electrolytes, that is, they conduct electricity when they dissolve in water. They turn blue litmus paper red.

Reactions

Reactions Between Metals and Acids

Acids + metal oxide(bases) ➡️ salt + water

Dilute acids + carbonates + hydrogen-carbonates ➡️ salt + carbon dioxide + water

ionization of acid in water

Basicity

  The maximum number of hydrogen ions produced by one molecule of the acid is called the basicity of the acid. Acids that can give more than one hydrogen ion per molecule are called poly-basic acids.

mono-basic acid, dibasic acid and tribasic acid

Alkalis

  Bases are 'chemical opposites' of acids. Metal oxides and metal hydroxides are bases. A few bases are soluble in water, and they are called alkalis. Ammonia is also an alkali. Alkalis are also electrolytes, and they turn red litmus paper blue.

Reactions

dissociation of alkalis

alkalis + acids ➡️ salt + water (neutralization, exothermic)

alkalis + carbon dioxide ➡️ metal carbonate + water

alkalis + salt(solution) ➡️ metal hydroxides(precipitation) + new salt (solution)

reactions of alkalis and ammonium compounds

Precipitates That Redissolve in Excess Sodium Hydroxide Solution

Aluminum hydroxide, zinc hydroxide and lead(II) hydroxide dissolve in excess sodium hydroxide solution; zinc hydroxide and copper(II) hydroxide dissolve in excess aqueous ammonia. This is because soluble complex ions are formed after reaction.

Equations of precipitates redissolving