Science : Ch 02 – Acids Bases and Salts

Calcium phosphate Ca₃(PO₄)₂  is a basic salt, as it is formed by the combination of a weak acid (phosphoric acid) and a slightly stronger base (calcium hydroxide)

The increasing order of acid strength is water < acetic acid < hydrochloride acid. Hydrochloride acid is a strong acid and ionises fully in water.

Phenolphthalein solution is a colourless indicator which gives pink colour in basic solution. Phenolphthalein solution remains colourless in acidic solution as well as in neutral solution.

washing the hands with water will dilute the acid and wash it out. Any remaining acid will be neutralized with sodium hydrogen carbonate (baking soda) as it is a base. This will minimize the effect of damage caused by acid to the skin.

Sodium carbonate (Na₂CO₃) is the salt of carbonic acid (H₂CO₂) and sodium hydroxide (NaOH). Here NaOH is a powerful base and carbonic acid is a weak acid.

Chloralkali process is an industrial process that is used to form sodium hydroxide by electrolysis of aqueous solution of sodium chloride NaCl

C₂H₅OH is not a base. C₂H₅OH is an organic compound with –OH functional group that is known as alcohol

When a small amount of acid such as hydrochloric acid is added to water, individual ions of the acid are dissociated This process is known as ionisation.

On a pH scale acidity ranges from 1 to 7 and it increases by moving down from 7 to 1 while basicity ranges from 7 to 14 which increases by moving up from 7 to 14.

When an acid responds with a base, a neutral salt is formed by the neutralisation process. As the neutralisation process is an exothermic reaction, the temperature of the solution become greater.

HCI, being a polar covalent compound, easily ionses in water to form hydronium (H₃O+) and chloride ions (Cl– ). HCl (a strong acid) ionises completely in water to produce H+ and Cl–  ions. H+ ion dilutes with water molecules to produce hydronium ions.