Calculate the mass of sulfuric acid required to neutralize 200 g of 20% sodium hydroxide solution.

1) The equation of the reaction H2SO4 + 2NaOH = Na2SO4 + 2H2O
2) The mass of sodium hydroxide is calculated
m (NaOH) = 200 * 20/100 = 40 (g)
3) Found the mass of sulfuric acid m (H2SO4) = 98 * 40/80 = 49 (g)

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