When 1.800 grams of anhydrous magnesium chloride were exposed to moist air,water was absorbed by the sample.If the resulting hydrated compound has a mass of 2.481 grams,what is the chemical formula of the hydrate? A)MgCl₂∙ H₂O B)MgCl₂∙ 2H₂O C)MgCl₂∙ 3H₂O D)MgCl₂∙ 4H₂O

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Quizplus · Accepted Answer

The mass of water absorbed is 2.481 g - 1.800 g = 0.681 g. The molar mass of MgCl2 is 95.21 g/mol, so 1.800 g is 0.0189 mol. The molar mass of water is 18.02 g/mol, so 0.681 g is 0.0378 mol. The ratio of moles of water to moles of MgCl2 is approximately 2:1, indicating the formula MgCl2∙2H2O.

When 1800 Grams of Anhydrous Magnesium Chloride Were Exposed to Moist