Solve for x chem problem

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Epsom salts, a strong laxative used in veterinary medicine, is a hydrate, which means that a certain number of water molecules are included in the solid structure. The formula for Epsom salts can be written as MgSO4 · x H2O, where x indicates the number of moles of H2O per mole of MgSO4. When 3.590 g of this hydrate is heated to 250°C, all the water of hydration is lost, leaving 1.753 g of MgSO4. What is the value of x?

Jul 24th, 2015

solution

the molar mass of MgSO4 which is 120.38 grams. 2.471g/120.38g/mol = 0.020534 mols of MgSO4.

how many moles of water were lost when you heated the Epsom Salt?

5.061g - 2.472g = 2.589 g.

Same process as for the MgSO4.

The molar mass of H2O is 18.00g/mol. So 2.589/18.00g/mol = 0.1438 mols.

So

0.1438 mols/0.020534 mols MgSO4 = 7.005.

Which rounds to 7

So your formula is MgSO4 * 7 H2O.

Jul 24th, 2015

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Jul 24th, 2015
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Jul 24th, 2015
Dec 4th, 2016
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