An excess of barium nitrate solution was added to a solution of sodium sulfate with a volume of 250
An excess of barium nitrate solution was added to a solution of sodium sulfate with a volume of 250 ml with a mass fraction of Na2SO4 equal to 7.60% and a density of 1.080 g / cm. Determine the mass of the precipitate formed.
Find the mass of the Na2SO4 solution.
m = Vp.
m = 250 cm3 × 1.080 g / cm3 = 270 g.
Find the mass of Na2SO4 in solution.
W = m (substance): m (solution) × 100%,
m (substance) = (m (solution) × W): 100%.
m (Na2SO4) = (270 g × 7.6%): 100% = 20.52 g.
Let’s find the amount of the substance Na2SO4 by the formula:
n = m: M.
M (Na2SO4) = 142 g / mol.
n = 20.52 g: 142 g / mol = 0.14 mol.
Let’s compose the reaction equation, find the quantitative ratios of substances.
Na2SO4 + Ba (NO3) 2 = BaSO4 ↓ + 2NaNO3.
According to the reaction equation, there is 1 mol of BaSO4 for 1 mol of Na2SO4. Substances are in quantitative ratios 1: 1.
n (Na2SO4) = n (BaSO4) = 0.14 mol.
Let’s find the mass of BaSO4 by the formula:
m = n × M,
M (BaSO4) = 233 g / mol.
m = 0.14 mol × 233 g / mol = 32.62 g.
Answer: 32.62 g.