Alum is a hydrated compound containing 45.5% water. How many moles of water are contained in one mole of this hydrate.
Data for alum
M= 474 g∙mol-1
To find the number of moles of water contained in one mole of the hydrate, we need to first determine the molar mass of water.
The molar mass of water (H2O) is:
H = 1.01 g/mol
O = 16.00 g/mol
So, the molar mass of water (H2O) is:
(2 * 1.01) + 16.00 = 18.02 g/mol
Now, we can use the information given to calculate the moles of water in one mole of alum.
Alum is a hydrated compound containing 45.5% water. This means that 45.5% of the total mass of alum is water.
The molar mass of alum (Al2(SO4)3 * xH2O) is given as 474 g/mol.
To find the mass of water in one mole of alum, we can multiply the molar mass of alum by the percentage of water:
Mass of water = (45.5/100) * 474 g/mol = 215.77 g
Now, we can calculate the moles of water in one mole of alum by dividing the mass of water by the molar mass of water:
Moles of water = mass of water / molar mass of water
= 215.77 g / 18.02 g/mol
≈ 11.975 mol
Therefore, one mole of this hydrate contains approximately 11.975 moles of water.