Question 1

Which of the following best explains why transition metals often exhibit variable oxidation states?

Accepted Answer

Their d orbitals are partially filled and have similar energies, allowing electrons to be lost from both s and d orbitals.

Question 2

What is the electronic configuration of Fe$$^{3+}$$?

Accepted Answer

$$[Ar] 3d^5$

Question 3

Which property of transition metals is primarily responsible for their use as catalysts?

Accepted Answer

Ability to form variable oxidation states and complex ions

Question 4

Which of the following ions is most likely to form a blue solution in water?

Accepted Answer

Cu$$^{2+}$$

Question 5

Given the complex ion $$[Fe(CN)_6]^{4-}$$, what is the oxidation state of Fe?

Accepted Answer

+2

Question 6

Which of the following best describes the trend in first ionization energies across the fourth period d-block elements?

Accepted Answer

They generally increase with some irregularities due to electron configurations.

Question 7

Which oxide of manganese is acidic in nature?

Accepted Answer

Mn$$_2O$_7$$

Question 8

What is the coordination number of the central metal ion in $$[Cr(NH_3$)_6]^{3+}$$?

Accepted Answer

6

Question 9

Which of the following is a correct statement about the colour of transition metal complexes?

Accepted Answer

The colour depends on the metal ion, its oxidation state, and the nature of the ligands.

Question 10

Which of the following reactions correctly represents the reduction of $$Cr_2O_7$$^{2-}$$ in acidic medium?

Accepted Answer

$$Cr_2O_7$$^{2-}$$ + 14H^+ + 6e^- \rightarrow 2Cr$$^{3+}$$ + 7H_2O$$

Question 11

Which of the following is NOT a typical property of d-block elements?

Accepted Answer

Lack of catalytic activity

Question 12

What is the oxidation state of chromium in $$K_2Cr_2O_7$$?

Accepted Answer

+6

Question 13

Which of the following best explains why $$Zn^{2+} is $$colourless in aqueous solution?

Accepted Answer

It has a completely filled d subshell ($$3d^{10}$$), so no d-d transitions occur.

Question 14

Which of the following ligands is considered a neutral ligand in coordination chemistry?

Accepted Answer

NH$$_3$$

Question 15

What is the colour of $$[Co(NH_3$)_6]^{2+} in $$aqueous solution?

Accepted Answer

Blue

Question 16

Which of the following is a correct IUPAC name for the complex $$[Fe(CN)_6]^{3-}$$?

Accepted Answer

Hexacyanoferrate(III) ion

Question 17

Which of the following factors does NOT affect the colour of a transition metal complex?

Accepted Answer

Type of solvent

Question 18

Which of the following is a common oxidation state for copper in its compounds?

Accepted Answer

+1 and +2

Question 19

Which of the following best describes the role of ligands in the formation of coordination compounds?

Accepted Answer

Ligands donate electrons to the central metal ion to form coordinate covalent bonds.

Question 20

Which of the following is the correct formula for the complex ion formed when cobalt(II) reacts with excess ammonia?

Accepted Answer

$$[Co(NH_3$)_6]^{2+}$$

Chemistry of 3d, 4s, and 4p Block Elements: Properties, Complexes, and Reactions

Study Guide - Practice Questions