Arrange the following in ascending order of their valency
Boron,Beryllium and Lithium.
Oxygen, Ammonium Chloride, Sulphuric acid.
Boron:
It has 3 electrons in it's outermost orbit and can give 3 electrons inspite of gaining 5 electrons. So it's valency is 3.
Beryllium;
It has 2 electrons in the outermost orbit and can give 2 electrons inspite of gaining 6 electrons . So it's valency is 2.
Lithium:
It has 1 electron in the outermost orbit and can give 1 electron inspite of gaining 7 electrons . So it's valency is 1.