Write down the formula of the black precipitate formed when `H_2S` gas is passed through an aqueous solution of lead nitrate?

SO_(2) gas is passed through a clear solution of lime water.

H_(2) gas is passed through CuSO_(4) solution

F_(2) gas is passed through 2% NaOH solution.

Why does not ZnS get precipitated when H_2S is passed through an acidic solution of Zn -salt?

H_(2)S gas is passed through chlorine -water .

When I_(2) is passed through KCl, KF and KBr solution

What change of colour is observed when H_2S gas is passed through an acidified aqueous solution of potassium dichromate?

In qualitative analysis, a black precipitate is obtained when H_(2)S is passed through an acidified aqueous solution of a salt . A blue coloured solution is obtained on boiling the preciptate with dilute HNO_(3) . The substance obtained on addition of excess of ammonia solution to this blue solution is -

State, with equations, what happens when O_(3) gas is passed through an aqueous solution of Kl.

Explain what happens when HCl gas is passed through saturated solution of NaCl .