Question
What is the percentage composition by mass of water of crystallization in hydrated magnesium chloride?
Answers
GPT 3.5
The formula for hydrated magnesium chloride is MgCl2·xH2O, where x represents the number of water molecules associated with each magnesium chloride molecule. To find the percentage composition of water, we need to calculate the ratio of the mass of water to the total mass of the compound and then express it as a percentage.
Let's assume the value of x is unknown for now.
The molar mass of MgCl2 is 24.31 g/mol (magnesium) + 2 * 35.45 g/mol (chlorine) = 95.21 g/mol.
The molar mass of H2O is 2 * 1.01 g/mol (hydrogen) + 16.00 g/mol (oxygen) = 18.02 g/mol.
Now, let's consider one mole (1 mol) of hydrated magnesium chloride:
Molar mass of one mole of MgCl2 = 95.21 g/mol.
Molar mass of one mole of xH2O = 18.02 g/mol * x.
The percentage composition of water can be calculated using the formula:
(18.02 g/mol * x) / (95.21 g/mol + 18.02 g/mol * x) * 100.
We do not know the value of x yet, but we can find it using additional information. The molar mass of hydrated magnesium chloride is given as 203.3 g/mol.
203.3 g/mol = 95.21 g/mol + 18.02 g/mol * x.
Let's solve for x:
203.3 g/mol - 95.21 g/mol = 18.02 g/mol * x,
108.09 g/mol = 18.02 g/mol * x,
x = 108.09 g/mol / 18.02 g/mol ≈ 6.
Now, we can substitute the value of x into the percentage composition formula:
(18.02 g/mol * 6) / (95.21 g/mol + 18.02 g/mol * 6) * 100.
(108.12 g/mol) / (203.3 g/mol) * 100 ≈ 53.15%.
Therefore, the percentage composition by mass of water of crystallization in hydrated magnesium chloride is approximately 53.15%.
Let's assume the value of x is unknown for now.
The molar mass of MgCl2 is 24.31 g/mol (magnesium) + 2 * 35.45 g/mol (chlorine) = 95.21 g/mol.
The molar mass of H2O is 2 * 1.01 g/mol (hydrogen) + 16.00 g/mol (oxygen) = 18.02 g/mol.
Now, let's consider one mole (1 mol) of hydrated magnesium chloride:
Molar mass of one mole of MgCl2 = 95.21 g/mol.
Molar mass of one mole of xH2O = 18.02 g/mol * x.
The percentage composition of water can be calculated using the formula:
(18.02 g/mol * x) / (95.21 g/mol + 18.02 g/mol * x) * 100.
We do not know the value of x yet, but we can find it using additional information. The molar mass of hydrated magnesium chloride is given as 203.3 g/mol.
203.3 g/mol = 95.21 g/mol + 18.02 g/mol * x.
Let's solve for x:
203.3 g/mol - 95.21 g/mol = 18.02 g/mol * x,
108.09 g/mol = 18.02 g/mol * x,
x = 108.09 g/mol / 18.02 g/mol ≈ 6.
Now, we can substitute the value of x into the percentage composition formula:
(18.02 g/mol * 6) / (95.21 g/mol + 18.02 g/mol * 6) * 100.
(108.12 g/mol) / (203.3 g/mol) * 100 ≈ 53.15%.
Therefore, the percentage composition by mass of water of crystallization in hydrated magnesium chloride is approximately 53.15%.