State how you would prove that HCl contains :

(i) hydrogen – using an active metal below magnesium

(ii) chlorine – using an oxidising agent not containing lead.

State the composition of aqua regia. State which component is the oxidising agent in aqua regia.

State why aqua regia dissolves gold, which is insoluble in all other acids.

Give three tests for hydrochloric acid. Convert silver nitrate to a soluble salt of silver using hydrochloric acid and an alkali.