When 3.600 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 4.962 grams,what is the chemical formula of the hydrate? A)MgCl₂∙ H₂O B)MgCl₂∙ 2H₂O C)MgCl₂∙ 3H₂O D)MgCl₂∙ 4H₂O

Question

Quizplus · Accepted Answer

We can calculate the amount of water that was absorbed by subtracting the mass of the anhydrous sample from the mass of the hydrated sample: 4.962 g - 3.600 g = 1.362 g of water. To determine the formula of the hydrate, we need to find the ratio of moles of magnesium chloride to moles of water.

First, we need to convert the masses to moles:
- Moles of anhydrous MgCl2 = 3.600 g / 95.21 g/mol = 0.03783 mol
- Moles of water = 1.362 g / 18.015 g/mol = 0.07561 mol

The ratio of moles of MgCl2 to water is approximately 1:2, which means the formula of the hydrate is MgCl2·2H2O. Converted to the format given in the answer choices, this corresponds to choice B: MgCl2·2H2O.

When 3600 Grams of Anhydrous Magnesium Chloride Were Exposed to Moist