Question

3. Which is the correct relationship:
(a) E1 (H)=1/2 E2 of (He+)=1/3 E3 (Li2+)=1/4 E4(Be3+)
(b) E1(H) = E2(He+) = E3(Li2+) = E4(Be3+)
(c) E1 (H) = 2E2(He+) = 3E3 (Li2+) = 4E4(Be3+)
(d) None of these​

Answer 1

Given: (a) E1 (H)=1/2 E2 of (He+)=1/3 E3 (Li2+)=1/4 E4(Be3+)

           (b) E1(H) = E2(He+) = E3(Li2+) = E4(Be3+)

           (c) E1 (H) = 2E2(He+) = 3E3 (Li2+) = 4E4(Be3+)

           (d) None of these​

To find: Which is the correct one?

Solution:

• Now we have given four options, those are:
• Now we know that E(n) = -13.6 Z^2 / n^2 eV/atom
• For H atom, E1 will be:

                   -13.6 x 1^2 / 1^2 =  -13.6 eV/atom

• For He+ atom, E2 will be:

                    -13.6 x 2^2 / 2^2 =  -13.6 eV/atom

• For Li2+ atom, E3 will be:

                    -13.6 x 3^2 / 3^2 =  -13.6 eV/atom

• For Be3+ atom, E4 will be:

                    -13.6 x 4^2 / 4^2 =  -13.6 eV/atom

• So all are same.

• So the correct option is second.

                    E1(H) = E2(He+) = E3(Li2+) = E4(Be3+)

Answer:

             So the correct option is B. E1(H) = E2(He+) = E3(Li2+) = E4(Be3+)