Question
What is the % composition by mass of water of crystallization in hydrated magnesium chloride?
Answers
GPT 3.5
The chemical formula for hydrated magnesium chloride is MgCl2·xH2O, where x represents the number of water molecules per formula unit. To find the % composition by mass of water of crystallization, we need to determine the molar mass of water and the molar mass of the entire compound.
The molar mass of water (H2O) is calculated by adding together the atomic masses of hydrogen (H) and oxygen (O):
Molar mass(H2O) = 2(1.008 g/mol) + 16.00 g/mol
= 18.016 g/mol
The molar mass of hydrated magnesium chloride (MgCl2·xH2O) is calculated by adding together the atomic masses of magnesium (Mg), chlorine (Cl), and water:
Molar mass(MgCl2·xH2O) = molar mass(Mg) + 2(molar mass(Cl)) + x(molar mass(H2O))
Given that the atomic masses are:
Molar mass(Mg) = 24.305 g/mol
Molar mass(Cl) = 35.453 g/mol
Substituting these values into the equation, we have:
Molar mass(MgCl2·xH2O) = 24.305 g/mol + 2(35.453 g/mol) + x(18.016 g/mol)
To find the % composition by mass of water of crystallization, we need to divide the molar mass of water by the molar mass of the entire compound and multiply by 100:
% composition by mass of water = (x(18.016 g/mol) / Molar mass(MgCl2·xH2O)) * 100
Therefore, the % composition by mass of water of crystallization in hydrated magnesium chloride can be calculated once the value of x is known.
The molar mass of water (H2O) is calculated by adding together the atomic masses of hydrogen (H) and oxygen (O):
Molar mass(H2O) = 2(1.008 g/mol) + 16.00 g/mol
= 18.016 g/mol
The molar mass of hydrated magnesium chloride (MgCl2·xH2O) is calculated by adding together the atomic masses of magnesium (Mg), chlorine (Cl), and water:
Molar mass(MgCl2·xH2O) = molar mass(Mg) + 2(molar mass(Cl)) + x(molar mass(H2O))
Given that the atomic masses are:
Molar mass(Mg) = 24.305 g/mol
Molar mass(Cl) = 35.453 g/mol
Substituting these values into the equation, we have:
Molar mass(MgCl2·xH2O) = 24.305 g/mol + 2(35.453 g/mol) + x(18.016 g/mol)
To find the % composition by mass of water of crystallization, we need to divide the molar mass of water by the molar mass of the entire compound and multiply by 100:
% composition by mass of water = (x(18.016 g/mol) / Molar mass(MgCl2·xH2O)) * 100
Therefore, the % composition by mass of water of crystallization in hydrated magnesium chloride can be calculated once the value of x is known.