Lakhmir Singh and Manjit Kaur Solutions for Chapter: Atomic Structure, Exercise 4: EXERCISES

Valency is always a whole number. 

Acid radical has positive valency.

Valency of sulphate in ${\mathrm{H}}_2{\mathrm{SO}}_4$ is $-2$.

Periodic table has seven groups. 

An element belongs to a group $18$ and a second period. Identify the element and write its valency and number of valence electrons.

Calculate the number of atoms present in:

One molecule of ${\mathrm{HNO}}_3$

Calculate the number of atoms present in:

One molecule of ${\mathrm{CaCO}}_3$.

Calculate the number of atoms present in:

One molecule of ${\mathrm{CH}}_3\mathrm{COOH}$.