Question

Copper (II) sulfate (CuSO4) forms a hydrate. If 4.56 g of the hydrate yields 2.92 g of anhydrous CuSO4, what is the correct name for the hydrate?

Answer 1

the formula hydrate salt = CuSO4.5H20 which is known as copper (ii) sulfate pentahydrate

Answer 2

The correct name for the hydrate salt is calculated as follows

calculate the mass of water =mass of hydrated salt- mass of anhydrous salt

4.56-2.92=1.64g
mass of anhydrous salt (CuSo4)= 2.92g

calculate the mole of water and anhydrous salt
that is
moles =mass/molar mass
moles of water = 1.64g/18g/mol= 0.0911 moles

moles of CUSO4 =2.92g/ 159.5 g/mol=0.0183 moles

find the moles ratio by dividing with the smallest moles that is 0.0183 moles

for H20 = 0.0911/0.0183= 5
CuSO4 = 0.0183/0.0183=1

the formula hydrate salt = CuSO4.5H20 which is known as copper (ii) sulfate pentahydrate