A 31.5 mL aliquot of HNO₃ (aq)of unknown concentration was titrated with 0.0134 M NaOH (aq).It took 23.9 mL of the base to reach the endpoint of the titration.The concentration (M)of the acid was ________. A)0.0102 B)0.0051 C)0.0204 D)0.227 E)1.02

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The correct answer is A because:The balanced chemical equation for the reaction is:HNO₃ (aq) + NaOH (aq) → NaNO₃ (aq) + H₂O (l)The moles of NaOH used in the titration are:0.0134 M NaOH x 0.0239 L NaOH = 0.000320 mol NaOHAccording to the balanced chemical equation, 1 mol of HNO₃ reacts with 1 mol of NaOH. Therefore, the moles of HNO₃ in the aliquot are also 0.000320 mol.The concentration of the HNO₃ solution is:0.000320 mol HNO₃ / 0.0315 L HNO₃ = 0.0102 M HNO₃

A 315 ML Aliquot of HNO3 (Aq)of Unknown Concentration Was Titrated

A 315 ML Aliquot of HNO₃ (Aq)of Unknown Concentration Was Titrated