Mixed 52.6 ml of a 25% solution of aluminum sulfate (pl. 1.3 g / ml) and a solution of barium
Mixed 52.6 ml of a 25% solution of aluminum sulfate (pl. 1.3 g / ml) and a solution of barium chloride. Calculate the mass of the precipitate formed.
1. Al2 (SO4) 3 + 3BaCl2 = 3BaSO4 + 2AlCl3;
2.m (solution Al2 (SO4) 3) = ρ (solution Al2 (SO4) 3) * V (solution Al2 (SO4) 3);
m (solution Al2 (SO4) 3) = 1.3 * 52.6 = 68.38 g;
3.m (Al2 (SO4) 3) = w (Al2 (SO4) 3) * m (solution Al2 (SO4) 3);
m (Al2 (SO4) 3) = 0.25 * 68.28 = 17.095 g;
4.find the chemical amount of aluminum sulfate:
n (Al2 (SO4) 3) = m (Al2 (SO4) 3): M (Al2 (SO4) 3);
M (Al2 (SO4) 3) = 2 * 27 + 3 * 32 + 3 * 4 * 16 = 342 g / mol;
n (Al2 (SO4) 3) = 17.095: 342 = 0.05 mol
5.According to the reaction equation, the amount of precipitate obtained is three times greater than the consumed aluminum sulfate:
n (BaSO4) = 3 * n (Al2 (SO4) 3) = 3 * 0.05 = 0.15 mol;
6.Calculate the mass of the sediment:
m (BaSO4) = n (BaSO4) * M (BaSO4);
M (BaSO4) = 137 + 32 + 4 * 16 = 233 g / mol;
m (BaSO4) = 0.15 * 233 = 34.95 g.
Answer: 34.95 g.