Question

Account for the following :
A) PF5 is known, whereas NF5 is not. Explain.

B) F2 is a gas while I2 is a solid. Explain.

C) Out of H and H2, H has higher first ionisation energy while out of O and O2, O2 has higher first ionisation energy. Explain why?

Answer 1

Answer:

1)Due to the lack of valance orbital

Answer 2

Answer:

Explanation:

1 PF5 exist but NF5 not due to unavaiblity of d-orbital

2 F2 is gas due to weak dispersion forces btw them...I2 as larger LDP bcoz of large mass and hence exist as solid

3 H has config. ns1 very diff to take out e- & hence ΔHi= -ve

O2- has complte shell hence e- removal is hard so ΔHi= -ve