Question

Problem 12(c): Identify the first-row transition metal that

satisfies the requirements given:
[M(H2O)6]2+ expected to have
the palest color in aqueous solution.

Answer 1

The transition metal from the first row that would result in the palest color for the [M(H2O)6]2+ complex is zinc, due to its d10 electron configuration resulting in colorless complexes.

Step-by-step explanation:

The student's question pertains to identifying the first-row transition metal whose hexaaqua complex, [M(H2O)6]2+, is expected to exhibit the palest color in aqueous solution. To determine which transition metal ion would result in the palest color, we need to consider the electronic configuration of the metal ion's d-orbitals. Transition metals with a d0 or d10 configuration typically form colorless complexes, as there are no electron transitions that can absorb visible light. From the provided information and general chemistry knowledge, the hexaaquazinc ion, [Zn(H2O)6]2+, which has a d10 configuration, is expected to be colorless and therefore would be considered to have the palest color in solution.

Answer 2

The first-row transition metal that satisfies the given requirements is chromium(III). Transition metal ions can exhibit a wide variety of colors when dissolved in water.

Step-by-step explanation:

The first-row transition metal that satisfies the given requirements is chromium(III).

Transition metal ions can exhibit a wide variety of colors when dissolved in water. The color of a transition metal complex is determined by the energy difference between its d-orbitals. The higher the energy difference, the more intense the color.

In this case, the hexa-aquachromium(III) ion is expected to have the palest color in aqueous solution among the first-row transition metals.