Calculate the total number of electrons present in 1.6 g of methane.

A flask contains 3.2 g of ${\mathrm{SO}}_2$. Calculate

(i) the moles of sulphur dioxide present in the flask.

(ii) when ${\mathrm{SO}}_2$ present in flask reduce to 1.6 g, then moles of ${\mathrm{SO}}_2$ present in the flask.

(iii) the number of molecules of ${\mathrm{SO}}_2$ present in the flask.

(iv) the volume occupied by 3.2 g of ${\mathrm{SO}}_2$ at STP. 

Write the balanced chemical equation for the preparation of Iron $\left(\mathrm{II}\right)$ sulphate.

Write the balanced chemical equation for the preparation of Zinc sulphate.

Give the balanced chemical equation for ferric hydroxide reacts with nitric acid.

Give the balanced chemical equation for the preparation of sodium sulphate from sodium carbonate.

Give the balanced chemical equation for the action of $\mathrm{KOH}$on ${\mathrm{ZnSO}}_4$.

Identify the term or substance based on the description given below.

A chemical reaction in which electrons are lost by one substance and gained by another.