---
title: "A student heats a \\(1.56 \\text{ g}\\) sample of hydrated magnesium sulfate, \\(\\text{MgSO}_4 \\cdot x\\text{H}_2\\text{O(s)}\\), in a crucible until all water of hydration is driven off. The remaining anhydrous \\(\\text{MgSO}_4\\text{(s)}\\) has a mass of \\(1.20 \\text{ g}\\). The molar mass of \\(\\text{MgSO}_4\\) is \\(120 \\text{ g/mol}\\) and the molar mass of \\(\\text{H}_2\\text{O}\\) is \\(18 \\text{ g/mol}\\). What is the value of \\(x\\)?"
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url: "https://nerd-notes.com/ubq/119236/"
date_modified: "2026-08-19T12:39:30+00:00"
---

# A student heats a \(1.56 \text{ g}\) sample of hydrated magnesium sulfate, \(\text{MgSO}_4 \cdot x\text{H}_2\text{O(s)}\), in a crucible until all water of hydration is driven off. The remaining anhydrous \(\text{MgSO}_4\text{(s)}\) has a mass of \(1.20 \text{ g}\). The molar mass of \(\text{MgSO}_4\) is \(120 \text{ g/mol}\) and the molar mass of \(\text{H}_2\text{O}\) is \(18 \text{ g/mol}\). What is the value of \(x\)?

A student heats a \(1.56 \text{ g}\) sample of hydrated magnesium sulfate, \(\text{MgSO}_4 \cdot x\text{H}_2\text{O(s)}\), in a crucible until all water of hydration is driven off. The remaining anhydrous \(\text{MgSO}_4\text{(s)}\) has a mass of \(1.20 \text{ g}\). The molar mass of \(\text{MgSO}_4\) is \(120 \text{ g/mol}\) and the molar mass of \(\text{H}_2\text{O}\) is \(18 \text{ g/mol}\). What is the value of \(x\)?

- **A.** \(2\)
- **B.** \(3\)
- **C.** \(5\)
- **D.** \(7\)

*The answer key and step-by-step explanation are available to logged-in users at https://nerd-notes.com/ubq/119236/*