What mass of sodium hydroxide (NaOH) is required to neutralize 20 g of a 4.9% sulfuric acid solution (H2SO4)

1. Let’s write down the reaction equation:

2NaOH + H2SO4 = Na2SO4 + 2H2O.

2. Find the mass, and then the amount of sulfuric acid:

m (H2SO4) = (m (solution) * ω (H2SO4)) / 100% = 20 g * 4.9% / 100% = 0.98 g.

n (H2SO4) = m (H2SO4) / M (H2SO4) = 0.98 g / 98 g / mol = 0.01 mol.

3. Using the reaction equation, we find the amount of sodium hydroxide, and then its mass:

2n (NaOH) = n (H2SO4).

n (NaOH) = 0.5n (H2SO4) = 0.005 mol.

m (NaOH) = n (NaOH) * M (NaOH) = 0.005 mol * 40 g / mol = 0.2 g.

Answer: m (NaOH) = 0.2 g.