Question

Match the metals in Column II with their characteristic properties given in Column I.

• A. A = Q, B = R, C = S, D = P
• B. A = R, B = Q, C = S, D = P
• C. A = R, B = Q, C = P, D = S
• D. A = S, B = R, C = Q, D = P

Hint:

Remember: \(Sc^{3+}\) is colourless due to \(d^0\) configuration, and Gd is stable due to half-filled \(f\)-orbitals.

Answer 1

The Correct Option is A

Step 1: Identify lanthanoid with low \(3^{rd}\) ionisation enthalpy.
Gadolinium (Gd) has half-filled \(4f^7\) configuration after losing three electrons, which gives extra stability.
So,
\[ A \rightarrow Q. \]

Step 2: Identify f-block element with given configuration.
Configuration \([Rn]5f^2 6d^2 7s^2\) corresponds to Thorium (Th).
So,
\[ B \rightarrow R. \]

Step 3: Identify \(3d\)-series metal with colourless \(M^{3+}\).
Scandium (\(Sc^{3+}\)) has \(3d^0\) configuration, hence colourless.
So,
\[ C \rightarrow S. \]

Step 4: Identify metal with highest atomisation enthalpy.
Vanadium (V) has strong metallic bonding due to maximum number of unpaired electrons in \(3d\)-series, leading to high atomisation enthalpy.
So,
\[ D \rightarrow P. \]

Step 5: Write final matching.
\[ A = Q,\quad B = R,\quad C = S,\quad D = P. \]

Step 6: Match with options.
This corresponds to option (A).

Step 7: Final conclusion.
\[ \boxed{A = Q,\ B = R,\ C = S,\ D = P} \]