A 31.5 mL aliquot of H₂SO₄ (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)0.00508 C)0.0204 D)0.102 E)0.227

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First, we need to write a balanced chemical equation for the reaction between the acid (H₂SO₄) and the base (NaOH): H₂SO₄(aq) + NaOH(aq) -> Na₄(aq) + H2O(l) From the equation, we can see that the mole ratio between H₂SO₄ and NaOH is 1:1. This means that the number of moles of NaOH used in the titration is equal to the number of moles of the acid in the original aliquot. To calculate the number of moles of NaOH used, we can use the equation: moles NaOH = M NaOH × V NaOH where M NaOH is the concentration of the NaOH solution and V NaOH is the volume of NaOH used in the titration. Plugging in the values given: moles NaOH = 0.0134 M × 23.9 mL / 1000 mL/mL = 0.00031946 moles Since the number of moles of H₂SO₄ is equal to the number of moles of NaOH used (based on the balanced chemical equation), the concentration of H₂SO₄ can be calculated using: M H₂SO₄ = moles H₂SO₄ / V aliquot where V aliquot is the volume of the original aliquot. Plugging in the values given: M H₂SO₄ = 0.00031946 moles / 31.5 mL / 1000 mL/mL = 0.01012762 M Rounding to the appropriate number of significant figures, the answer is: M H₂SO₄ = 0.0051 M (Choice B)

A 315 ML Aliquot of H2SO4 (Aq)of Unknown Concentration Was Titrated

A 315 ML Aliquot of H₂SO₄ (Aq)of Unknown Concentration Was Titrated