Preparation of salts

What happens when a metal reacts with acid

Metal + acid → salt + hydrogen

Why is hydrogen gas produced when metal reacts with acid

The metal displaces hydrogen from the acid

How to make soluble salts from acids

Using metals by displacement reaction, insoluble oxide by neutralisation, using hydroxides by neutralisation

How to carry out crystallisation

Mix acid and base, warm on a tripod and gauze, filter the solution, evaporate the water using a water bath, leave it to dry

How to know if an acid and alkali have completely reacted

Use an indicator to measure ph

How to make ammonium salts

Reacts ammonia with water to form weakly alkaline solution, react ammonia solution with an acid

Ammonia and water reaction

NH3 + H2O → NH4+ + OH-

What is the function of ammonium salts

They contain a high proportion of nitrogen which is beneficial for plants

Precipitation reaction

A procedure of mixing solutions of two soluble salts to make an insoluble one

What is the purpose of insoluble salts in the water industry

Precipitation can be used to remove unwanted ions

Process of making an insoluble salt

Mix together two salts, filter the precipitate, wash the precipitate with distilled water to remove impurities

Sodium, potassium and ammonium

Soluble

Nitrates

Soluble

Chlorides

Soluble except silver chloride and lead chloride

Sulfates

Soluble except barium sulfate, calcium sulfate, lead sulfate

Carbonates

Insoluble except sodium carbonate, potassium carbonate, ammonium carbonate

Hydroxides

Insoluble except sodium hydroxide, potassium hydroxide, ammonium hydroxide