Question

please help urgent ( will rate)

hi the answer to these questions are ones ive circles but i just dont know why

and for the last question i dont understand the last part.

13. Arrange the following ions in order of increasing ion Collowing ions in order of increasing ionic radius: Cst, N., Be2. Te,00. A. Be2+< N3-<02- < Te2- < Cs+ B. N3-<02- < Te2. <Be2+ < Cs+ C. Be2+< N3-<02- <Cs+ < Te2 S isine D. Cs+ < Te2- < Be2+ < N3- <02- A 15², 25², 286, 35², 3P TID E. Be2+ < 02- <N3. < Cs+ < Te2.

Answer 1

Solution:

13) Option E

Ionic radius increases when we move from up to down in a group.

Ionic radius of same period elements increases with increasing negative charge and decreases with increasing positive charge.

A negatively charged ion has lesser number of protons in nucleus,  therefore nucleus exerted weak attraction to the electrons and increases the size. The positively charged ions posses smaller size due to high nuclear charge which causes strong attraction.

15) Option D

This question can be solved by simple thinking. The sigma 2s and sigma 2s* molecular orbitals are lying above the sigma 1s and sigma 1s* orbitals, hence they posses higher energy than lower orbitals.

Thus, option will be D because other options are smaller than or equal to 3.44 x 10^-21 J.

Note : Energy difference can not be zero between excited and nonexcited state.

Part C)

The calculated frequency in part B is low, hence can not perform excitation given in higher orbital excitations of part A.