# Cobalt (II) Chloride is commonly obtained from chemical suppliers as a hydrate. An analysis of...

## Question:

{eq}\displaystyle \rm Cobalt \ (II) \ Chloride {/eq} is commonly obtained from chemical suppliers as a hydrate. An analysis of {eq}\displaystyle \rm 25.0 \ g {/eq} of this hydrate was conducted by evaporating the water as described in this experiment. The anhydrous {eq}\displaystyle \rm cobalt \ (II) \ Chloride {/eq} mass was {eq}\displaystyle \rm 13.7 \ g {/eq}. Determine the formula of this hydrate.

## Cobalt(II) Chloride:

Cobalt(II) chloride can be used as an indicator for humidity. In its anhydrate form, cobalt(II) chloride is blue. In humid air, the cobalt(II) chloride will become hydrated by water molecules and turn red in the process. Some companies sell cobalt(II) chloride test strips for easy testing of humidity levels.

## Answer and Explanation: 1

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View this answerWe are told we initially have 25.0 g of a cobalt(II) chloride hydrate ({eq}\rm CoCl_2 \cdot xH_2O {/eq}). After heating, we have 13.7 g of the...

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Chapter 9 / Lesson 8Learn the anhydrate definition and what a hydrated compound is. Understand what an anhydrate is, the hydrate formula, and how to find the formula of the hydrate.

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