Question

Consider the following elements.

Which of the following is/are true about A',B',C'andD' ? A. Order of atomic radii: \( B' < A' < D' < C' \)
B. Order of metallic character: \( B' < A' < D' < C' \)
C. Size of the element: \( D' < C' < B' < A' \)
D. Order of ionic radii: \( B^{+} < A^{+} < D^{+} < C^{+} \)
Choose the correct answer from the options given below:

• A. A only
• B. A, B and D only
• C. A and B only
• D. B, C and D only

Answer 1

The Correct Option is B

To determine which statements are true about elements A', B', C', and D', we refer to the periodic trends:

1. Elements in the same period (row) are represented as A' and B'. The atomic radius typically decreases across a period from left to right due to the increasing nuclear charge that pulls electrons closer to the nucleus.
2. Elements in the same group (column) are represented as A', C', and D'. The atomic radius generally increases down a group due to the addition of electron shells.

Let's evaluate each option:

1. Option A: Order of atomic radii: \(B' < A' < D' < C'\)
   • This is true. Since A' is left of B' in the same period, \(B' < A'\). And since D' and C' are below A', \(A' < D' < C'\).
2. Option B: Order of metallic character: \(B' < A' < D' < C'\)
   • This is true. Metallic character decreases across a period and increases down a group. Hence, \(B' < A'\) and \(A' < D' < C'\).
3. Option C: Size of the element: \(D' < C' < B' < A'\)
   • This is false. As discussed, the atomic size increases down a group and decreases across a period.
4. Option D: Order of ionic radii: \(B^{+} < A^{+} < D^{+} < C^{+}\)
   • This is true, following the same general trends as atomic radii and taking into account the ionic charge effect.

Thus, the correct answer is: A, B, and D only.

Answer 2

Analysis of each statement:

Statement A: Order of atomic radii \(B' < A' < D' < C'\). The atomic radii decrease from left to right in a period and increase from top to bottom in a group. This order is correct.

Statement B: Order of metallic character \(B' < A' < D' < C'\). Metallic character decreases from left to right in a period and increases from top to bottom in a group. This order aligns with the general trend, so this statement is correct.

Statement C: Size of the element \(D' < C' < B' < A'\). This statement would be correct if we consider ionic sizes and periodic trends, but based on the provided context, this order does not match general atomic radius trends. This statement is incorrect.

Statement D: Order of ionic radii \(B^+ < A^{++} < D^{++} < C^{++}\). Ionic radii depend on the effective nuclear charge and the number of electrons lost. This order is correct based on typical ionic sizes across groups and periods.
Thus, the correct answer is: A, B, and D only.