# A chemist has a sample of hydrated FeCl_3 and it weighs 5.0 grams. He heats it strongly to drive...

## Question:

A chemist has a sample of hydrated {eq}FeCl_3{/eq} and it weighs {eq}5.0{/eq} grams. He heats it strongly to drive off water of hydration, and after heating, he found that the anhydrous compound has a mass of {eq}3.0{/eq} grams.

Find the formula of the hydrate.

## Water Of Crystallization

Some molecules, when forming crystals, absorb water from the surroundings and lock them into the crystal structure. However, this is not a chemical reaction: when heated strongly, this water of crystallization can be removed from the compound. The dry form is called 'anhydrous', while the one with water present is termed 'hydrated'.

## Answer and Explanation: 1

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View this answerWe can quantify the number of grams of water driven off by subtracting the mass of the anhydrous (water-less) form from the hydrated compound:

{eq}5....

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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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