Question

X belongs to IA or $1^{st}$ group and $5^{th}$ period and Y succeeds X in the group. Z succeeds Y in period. Arrange the following statements in the correct sequence in order to arrange X, Y and Z in the increasing order of their atomic sizes.
(a) Effect of number of valence electrons and number of shells on the atomic size.
(b) Identification of the elements X, Y, Z
(c) Determination of the number of shells and the number of valence electrons present in X, Y and Z.
(d) Determination of the positions of Y and Z in the periodic table based on the position of X.

• A. d b c a
• B. b d c a
• C. c a d
• D. d c a

Answer 1

The correct option is D d c a

(i) Determination of the positions of Y and Z in the periodic table based on the position of X.

(ii) Determination of the number of shells and the number of valence electrons present in X, Y and Z.

(iii) Effect of number of valence electrons and number of shells on the atomic size.

Option D is correct.