Chapter 17, Problem 17.1VP

Interpretation Introduction

Interpretation: The element that forms colored compounds with chloride ion in the given elements is to be stated.

Concept introduction: Cations form colored compounds when there is a presence of valence electrons in them which undergo transitions from ground state energy level to excited state energy level.

To determine: The element that forms colored compounds with chloride ion in the given elements.

Answer to Problem 17.1VP

Solution

The element that forms colored compounds with chloride ion is chromium.

Explanation of Solution

Explanation

The given Figure is,

Figure 1

In the Figure 1, the elements shown are calcium, chromium, cobalt and zinc. The transition metals form colored compounds because of the presence of more number of valence electrons. In the given elements, calcium forms ${\text{Ca}}^{\text{2+}}$ ions which form compound with chloride ion and give ${\text{CaCl}}_{\text{2}}$ which is a colorless solid.

Chromium forms ${\text{Cr}}^{\text{2+}}$ and ${\text{Cr}}^{\text{3+}}$ ions which form compounds with ${\text{Cl}}^{-}$ ion and they are colored compounds. Zinc element form ${\text{Zn}}^{\text{2+}}$ ions which form ${\text{ZnCl}}_{\text{2}}$ compound which is a colorless solid and cobalt also form colorless ${\text{CoCl}}_{\text{2}}$.

Hence, chromium forms colored compound with chloride ions.

Conclusion

The element that forms colored compounds with chloride ion is chromium.