This is a pre-lab question but I'm not sure if my teacher taught us how to solve these. Here's the Q...
The formula for Epsom salts is MgSO4 • 7H2O. If 1.250g of the compound is dissolved in water, calculate the number of milliliters of 0.200M Ba(NO3)2 that would be required to precipitate all of the sulfate ions as barium sulfate. (HINT: Start by writing a balanced equation.)
This is all i was given, if you could somehow help explain this to me it'd be great.
The formula for Epsom salts is MgSO4 • 7H2O. If 1.250g of the compound is dissolved in water, calculate the number of milliliters of 0.200M Ba(NO3)2 that would be required to precipitate all of the sulfate ions as barium sulfate. (HINT: Start by writing a balanced equation.)
This is all i was given, if you could somehow help explain this to me it'd be great.
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Ba(NO3)2 + MgSO4 • 7H2O ---------> BaSO4 + Mg(NO3)2 + 7 H2O
1.250 g MgSO4 • 7H2O x 1 mole MgSO4 • 7H2O/ 246.47 g MgSO4 • 7H2O = 5.072 x 10^-3 mole
Since there is a 1:1 molar relationship between MgSO4 • 7H2O and Ba(NO3)2, you need 5.072 x 10^-3 mole of Ba(NO3)2 as well. So 0.200 mole/1000 mL Ba(NO3)2 = 5.072 x 10^-3 mole/ x mL
x = 5.052/0.2 = 25.36 mL
1.250 g MgSO4 • 7H2O x 1 mole MgSO4 • 7H2O/ 246.47 g MgSO4 • 7H2O = 5.072 x 10^-3 mole
Since there is a 1:1 molar relationship between MgSO4 • 7H2O and Ba(NO3)2, you need 5.072 x 10^-3 mole of Ba(NO3)2 as well. So 0.200 mole/1000 mL Ba(NO3)2 = 5.072 x 10^-3 mole/ x mL
x = 5.052/0.2 = 25.36 mL