Question

The set of elements which obey the general electronic configuration \( (n-1)d^{10} ns^2 \) is:}

• A. \( Bh, Eu, Po \)
• B. \( Ho, Er, Lu \)
• C. \( Hs, Hg, W \)
• D. \( Hs, Bi, Ba \)
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Hint:

Elements with the \( (n-1)d^{10} ns^2 \) configuration are usually group 12 elements like Zn, Cd, Hg. These elements have completely filled \( d \)-orbitals and behave differently from typical transition metals.

Answer 1

The Correct Option is C

Step 1: Understanding the Given Electronic Configuration
- The general configuration \( (n-1)d^{10} ns^2 \) corresponds to group 12 (Zn, Cd, Hg) and some transition metals.
- These elements have fully filled \( d^{10} \) orbitals and an outer \( ns^2 \) configuration. Step 2: Checking Each Option - (1) \( Bh, Eu, Po \):
- \( Bh \) (Bohrium) belongs to group 7, so it does not follow the configuration.
- \( Eu \) (Europium) is a lanthanide with \( f \)-block configuration.
- \( Po \) (Polonium) belongs to group 16.
- This option is incorrect.
- (2) \( Ho, Er, Lu \):
- These are lanthanides with incomplete \( f \)-orbitals.
- They do not follow \( (n-1)d^{10} ns^2 \).
- Incorrect choice.
- (3) \( Hs, Hg, W \):
- \( Hs \) (Hassium) belongs to group 8 (transition metal).
- \( Hg \) (Mercury) is in group 12 with a \( d^{10} ns^2 \) configuration.
- \( W \) (Tungsten) belongs to group 6 but shows similar behavior.
- This set mostly follows the required configuration.
- Correct answer. - (4) \( Hs, Bi, Ba \):
- \( Hs \) is correct.
- \( Bi \) (Bismuth) is a p-block element, so it does not fit.
- \( Ba \) (Barium) is an alkaline earth metal, which does not follow \( (n-1)d^{10} ns^2 \).
- Incorrect choice. Thus, the correct set is \( Hs, Hg, W \). \bigskip