Find the mass of salt that is formed by draining 200g of 30% sodium hydroxide solution with a solution containing 49g of sulfuric acid
Find the mass of NaOH in solution.
W = m (substance): m (solution) × 100%,
m (substance) = (m (solution) × W): 100%.
m (NaOH) = (200 g × 30%): 100% = 60 g.
Find the amount of NaOH.
M (NaOH) = 40 g / mol.
n = m: M.
n = 60 g: 40 g / mol = 1.5 mol.
Let’s find the amount of the substance H2SO4.
M (H2SO4) = 98 g / mol.
n = m: M.
n = 49 g: 98 g / mol = 0.5 mol (deficiency).
Let’s compose the reaction equation. Let’s find the quantitative ratios of substances.
2 NaOH + H2SO4 = Na2SO4 + 2H2O.
According to the reaction equation, there is 1 mol of Na3PO4 for 1 mol of H2SO4. Substances are in quantitative ratios 1: 1.
The amount of substance Na3PO4 and H2SO4 are equal.
n (Na2SO4) = n (H2SO4) = 0.5 mol.
Find the mass of Na2SO4.
m = n × M,
M (Na2SO4) = 142 g / mol.
m = 0.5 mol × 142 g / mol = 71 g.
Answer: 71 g.
One of the components of a person's success in our time is receiving modern high-quality education, mastering the knowledge, skills and abilities necessary for life in society. A person today needs to study almost all his life, mastering everything new and new, acquiring the necessary professional qualities.