20.5 milliliters of 0.506 M NaOH is required to titrate 25.0 milliliters of sulfuric acid of unknown concentration.Find the molarity of the acid.

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The correct answer is A.20.5 mL of 0.506 M NaOH is required to titrate 25.0 mL of sulfuric acid of unknown concentration.The balanced chemical equation for the reaction is:H2SO4 + 2NaOH -> Na2SO4 + 2H2OFrom the balanced chemical equation, we can see that 1 mole of H2SO4 reacts with 2 moles of NaOH.Therefore, the number of moles of H2SO4 in 25.0 mL of the unknown solution is:(20.5 mL NaOH) x (0.506 mmol NaOH/mL NaOH) x (1 mmol H2SO4/2 mmol NaOH) = 5.18 mmol H2SO4The molarity of the unknown sulfuric acid solution is:(5.18 mmol H2SO4) / (25.0 mL H2SO4) = 0.207 MTherefore, the molarity of the acid is 0.207 M.

205 Milliliters of 0