Coordination Compounds Chapter-Wise Test 18

Correct answer Carries: 4.

Wrong Answer Carries: -1.

What is the oxidation state of cobalt in \( \ce{[Co(H2O)6]SO4} \)?

In \( \ce{[Co(H2O)6]SO4} \), \( \ce{H2O} \) is neutral, and \( \ce{SO4^2-} \) has a -2 charge. The complex \( \ce{[Co(H2O)6]^2+} \) balances this, so Co’s oxidation state is +2.

+2
+3
+1
+4
1

What is the ratio of \( e_g \) to \( t_{2g} \) electrons in \( \ce{[Fe(H2O)6]^2+} \) with Fe in +2 state? (Fe atomic number = 26)

Fe\(^{2+}\) (\( d^6 \)), weak field \( \ce{H2O} \), octahedral, high spin: \( t_{2g}^4 e_g^2 \). Ratio = 2 : 4 = 1 : 2.

1 : 1
2 : 3
1 : 2
3 : 2
3

How many moles of \( \ce{AgCl} \) precipitate when 1 mole of \( \ce{[Fe(NH3)5Cl]Cl2} \) reacts with excess \( \ce{AgNO3} \)?

In \( \ce{[Fe(NH3)5Cl]Cl2} \), the 2 \( \ce{Cl^-} \) ions outside the coordination sphere are ionizable and form \( \ce{AgCl} \), while the inner \( \ce{Cl} \) is a ligand. Thus, 2 moles precipitate.

2
1
3
0
1

The EAN of Cr in \( \ce{[Cr(NH3)5Cl]^2+} \) is: (Cr atomic number = 24)

Cr\(^{2+}\) with 5 \( \ce{NH3} \) and 1 \( \ce{Cl^-} \) (6 ligands). EAN = 24 - 2 + 2 × 6 = 34.

36
32
34
38
3

What is the IUPAC name of \( \ce{[Cr(NH3)5NO2]Cl2} \)?

Ligands: ammine (\( \ce{NH3} \)), nitro (\( \ce{NO2^-} \)), alphabetically ordered. Cr is +3 (balancing 2 \( \ce{Cl^-} \) and 1 \( \ce{NO2^-} \)). Name: pentaamminenitrochromium(III) chloride.

Pentaamminenitrochromium(III) chloride
Pentaamminenitrochromium(II) chloride
Nitropentaamminechromium(III) dichloride
Pentaamminenitrochromate(III) chloride
1

Which of the following is a heteroleptic complex?

A heteroleptic complex has different types of ligands. \( \ce{[Co(NH3)5Cl]^2+} \) has \( \ce{NH3} \) and \( \ce{Cl^-} \), unlike \( \ce{[Co(NH3)6]^3+} \) (homoleptic).

\( \ce{[Co(NH3)6]^3+} \)
\( \ce{[Co(NH3)5Cl]^2+} \)
\( \ce{[Fe(CN)6]^4-} \)
\( \ce{[Ni(CO)4]} \)
2

Which complex exhibits geometrical isomerism?

\( \ce{[Ni(NH3)2Cl2]} \) (square planar, \( \ce{[Ma2b2]} \)) has 2 \( \ce{NH3} \) and 2 \( \ce{Cl^-} \), allowing cis and trans isomers.

\( \ce{[Ni(CO)4]} \)
\( \ce{[Ni(NH3)2Cl2]} \)
\( \ce{[Co(NH3)6]^3+} \)
\( \ce{[Fe(CN)6]^4-} \)
2

Which complex has a \( d^8 \) metal ion that prefers square planar geometry over tetrahedral with strong field ligands?

\( \ce{[Ni(CN)4]^2-} \) (Ni\(^{2+}\), \( d^8 \)) with strong field \( \ce{CN^-} \) adopts square planar geometry, unlike tetrahedral with weak field ligands.

\( \ce{[CoCl4]^2-} \)
\( \ce{[Ni(CN)4]^2-} \)
\( \ce{[Fe(H2O)6]^2+} \)
\( \ce{[Cr(NH3)6]^3+} \)
2

Which complex would turn colorless if all its ligands were replaced by \( \ce{CN^-} \)?

\( \ce{[Ni(H2O)6]^2+} \) (Ni\(^{2+}\), \( d^8 \)) is colored (green) due to d-d transitions with weak field \( \ce{H2O} \). With strong field \( \ce{CN^-} \) (e.g., \( \ce{[Ni(CN)6]^4-} \)), it becomes low spin (diamagnetic), no d-d transitions, colorless.

\( \ce{[Co(CN)6]^3-} \)
\( \ce{[Ni(H2O)6]^2+} \)
\( \ce{[Fe(CN)6]^4-} \)
\( \ce{[Cr(NH3)6]^3+} \)
2

Which complex exhibits optical isomerism?

\( \ce{[Fe(en)2Cl2]^+} \) (octahedral) with 2 bidentate en and 2 \( \ce{Cl^-} \) can form a cis isomer that is chiral, lacking symmetry.

\( \ce{[Fe(H2O)6]^2+} \)
\( \ce{[NiCl4]^2-} \)
\( \ce{[Fe(en)2Cl2]^+} \)
\( \ce{[Cu(NH3)4]^2+} \)
3

Performance Summary

Score:

Category Details
Total Attempts:
Total Skipped:
Total Wrong Answers:
Total Correct Answers:
Time Taken:
Average Time Taken per Question:
Accuracy:
0