Question

The atom A, B, C have the configuration
A $\to$ [Z(90) + n(146)], B$\to$ [Z(92) + n(146)], C$\to$ [Z(90) + n(148)] So that
(a) A and C - Isotones (b) A and C - Isotopes
(c) A and B - Isobars (d) B and C - Isobars
(e) B and C - Isotones
The wrong statements are:

• A. a, b only
• B. c, d, e only
• C. a, c, d only
• D. a, d, e only

Answer 1

Answer: (D)

a, d, e only

	Z	A	A-Z
A	90	146	56
B	92	146	54
C	90	148	58

(a) A and C - are the atoms of same element. Hence, they cannot be isotones .
(b) A and C have same Z and different A. Hence they are isotopes.
(c) A and B have different Z but same A. Hence, they are isobars .
(d) B and C have different Z and A. Hence, they cannot be Isobars
(e) B and C have different A-Z values. Hence they cannot be Isotones Hence, the wrong statements are (a), (d) and (e).