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During the course of your experiment you have obtained the following data: mass of the hydrate: 1.973 g mass of the anhydrate: 1.196 g The formula of the anhydrous salt: CaCl2 Calculate the following: (round to correct the number of significant figures and include units as required). mass of water loss in . number of moles of anhydrous salt after heating, in moles number of moles of water lost, in moles • number of moles of water per mole of hydrate, in moles (round to the whole number) provide the formula of a hydrate Note: you will not be able to add the bscript and leave one space between ionic compound and water.

User Peter Bagyinszki
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Answer:

See explanation

Step-by-step explanation:

Mass of water lost = mass of hydrated salt - mass of anhydrous salt

Mass of water lost = 1.973 g - 1.196 g = 0.777g

Number of moles of water lost = 0.777g/18g/mol = 0.043 moles

Number of moles of anhydrous salt = 1.196 g /111g/mol = 0.011 moles

To obtain the number of moles of water of crystalization per hydrate molecule;

Number of moles of anhydrous salt = number of moles of hydrated salt

0.011 = 1.973 /111 + 18x

0.011(111 + 18x) = 1.973

1.221 + 0.198x = 1.973

0.198x = 1.973 - 1.221

x= 4

Hence, there are 4 moles of water per hydrate molecule. The formula of the hydrate is CaCl2.4H2O

User TechWisdom
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