The ratio of mass of 'x' atoms of an element to mass of carbon atoms is 9:1. Find the mass of 1 mol of x if molar mass of carbon is 12 g/mol.

What is the number of unpaired electrons present in ground state of Silicon and Chromium, respectively ?

Identify the most electronegative element by the following.

What is the total number of electrons present in bonding and antibonding orbitals respectively in $\text{F}_2$ molecule according to MO theory ?