How many electrons pairs are present in valence shell of oxygen in water molecule

How many electron pairs are present in valence shell of oxygen in wter molecule ?

How many electrons are present in the valence shell of P in PCl_3 ?

How many electrons are present in the valence shell of P in PCl_3 ?

How many electrons are there in valence shell of Mg atom?

How many electrons are presents in the outer shell of carbon?

How many electrons are present in the valence shells of the central atoms in the molecules of BeCl_(2), BF_(3) and PCl_(5) ?

The number of electron pairs present in the valence shell of central atom in SF_6 molecule are

How many lone pairs are present in nitrogen molecule ?