Two compounds of Iron are given below

FeSO4 , Fe2(SO4)3 (the oxidation state of sulphate radical is -2)

(a)Which of these compounds show +2 oxidation state for Iron?

(b) Which compound has Fe3+ ion?

(c)Write the subshell electronic configuration of Fe3+ ion.

(d) Why do the transition elements show variable oxidation states?

3. Identify the incorrect electronic configuration and correct them

(i) 1s2,2s2,2p3

(ii)1s2,2s2,2p6,3s1

(iii)1s2,2s2,2p6,2d7

(iv)1s2,2s2,2p6,3s2,3p6,3d4

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.