Calculate what mass of sulfuric acid is needed to neutralize 250 cm3. solution with a mass fraction

Calculate what mass of sulfuric acid is needed to neutralize 250 cm3. solution with a mass fraction of sodium hydroxide 20% and a density of 1.22 g / cm3

1. Let’s compose the equation of the chemical reaction:

2NaOH + H2SO4 = Na2SO4 + 2H2O.

2. Find the chemical amount of sodium hydroxide:

m (solution) = V (solution) * ρ (solution) = 250 m3 * 1.22 g / m3 = 305 g.

m (NaOH) = m (solution) * ω (NaOH) / 100% = 305 g * 20% / 100% = 61 g.

n (NaOH) = m (NaOH) / M (NaOH) = 61 g / 40 g / mol = 1.525 mol.

3. According to the reaction equation, we find the chemical amount, and then the mass of sulfuric acid:

n (H2SO4) = n (NaOH) / 2 = 0.76 mol.

m (H2SO4) = n (H2SO4) * M (H2SO4) = 0.76 mol * 98 g / mol = 74.73 g.

Answer: m (H2SO4) = 74.73 g.