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PLEASE HELP!Suppose you begin with 1.50~g of the hydrate copper(II)sulfate · x-hydrate (CuSO4· x H2O), where x is an integer. After dehydration you find that you are left with 0.96~g of the an-hydrate CuSO4. What is the unknown integer x. Round your answer to the nearest integer, enter only an integer.
Suppose you begin with of the hydrate KAl(SO4)2 · 12H2O. After dehydration you find that you are left with 3.0~g of the an-hydrate KAl(SO4)2. How many grams did you start with? Write the value to the correct number of significance figures.

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ChemistryHelper2024
For first problem:
mass of water = 1.5 g - 0.96 g = 0.54 g
mole of water = [tex] \frac{0.54 g}{18 g/mole} = 0.3 mol[/tex]
mole of CuSO₄ = [tex] \frac{0.96 g}{159.6 g/mole} = 6 x 10^{-3} mol [/tex]
mole of water / mole of anhydrate = [tex] \frac{0.03}{6 x 10^{-3}} = 5 [/tex] 
so x equal 5

For second problem:
After dehydration 12 H₂O evaporated decreasing mass by (12 x 18) = 216 g/mole
number of moles of KAl(SO₄)₂ = [tex] \frac{3}{258.2} = 0.0116 mol [/tex]
mass of evaporated water = 216 x 0.0116 = 2.5 g
Initial weight = 2.5 g + 3 g = 5.5 g

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