Question

Novelty devices for predicting rain contain colbalt chloride and are based on the following equilibrium:

CoCl2(s) + 6H2O(g) = CoCl2 . 6H2O(s)
First part of equilibrium is Purple
Second part of equilibrium is Pink
What color will such an indicator be if rain is imminent?

Answer 1

A rain-predicting novelty device with cobalt chloride will turn pink when rain is imminent, indicating increased humidity and the formation of hydrated cobalt(II) chloride.

Step-by-step explanation:

Novelty devices for predicting rain, which contain cobalt chloride (CoCl2), change color based on the humidity in the air due to the equilibrium reaction CoCl2(s) + 6H2O(g) = CoCl2 · 6H2O(s). The anhydrous cobalt(II) chloride is blue, and when it is hydrated with six molecules of water, it forms cobalt(II) chloride hexahydrate which is pink in color. If rain is imminent, the air is typically more humid, which means the CoCl2 will absorb more water and form the hydrated cobalt(II) chloride, indicating a color change to pink. This is a reversible reaction, highlighting the dynamic nature of chemical equilibria in response to changes in environmental conditions such as humidity.

Answer 2

Pink

Step-by-step explanation:

In the reaction, in the left part we have two species to react, but it is not reacting yet. While the right part of the reaction, we have one specie that is the product of the addition of two differents species.

The CoCl2 when is dry (anhydrus) the apparence is a purple-blue fine powder, while it chemical absorbs water (wold be wet) the apparence is a pink coarse powder.

I hope you undersant