# A 43.0 g sample of hydrated cobalt (II) sulfite is heated to drive off the water. The anhydrous...

## Question:

A 43.0 g sample of hydrated cobalt (II) sulfite is heated to drive off the water. The anhydrous cobalt (II) sulfite has a mass of 26.1 g.

a. Calculate the mass of water.

b. Calculate the moles of water.

c. Calculate the moles of cobalt (II) sulfite.

d. Calculate the mole ratio of water to cobalt (II) sulfite and write the correct formula.

## Hydrates:

Hydrates are ionic compounds that involve water in their crystal structures. To find the hydration number of the material, you can heat the material until the water is driven off and compare the mass of evaporated water to the mass of remaining anhydrous salt.

## Answer and Explanation: 1

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#### Question (a)

The mass of water is just the difference between the initial and final mass of the sample.

{eq}\rm m_{H_2O} = m_i - m_f = 43.0 g -...

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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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