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?

Pink

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

i believe it is c.) 1575 j.