A solution of the primary standard potassium hydrogen phthalate (KHP), KHC8H4O4 , was prepared by dissolving 0.4877 g of KHP in about 50 mL

Question

A solution of the primary standard potassium hydrogen phthalate (KHP), KHC8H4O4 , was prepared by dissolving 0.4877 g of KHP in about 50 mL of water. Titration of the KHP solution with a KOH solution of unknown concentration required 28.49 mL to reach a phenolphthalein end point. What is the concentration of the KOH solution?

in progress 0
Xavia 5 years 2021-07-15T15:40:04+00:00 1 Answers 70 views 0

Answers ( )

    0
    2021-07-15T15:41:58+00:00

    Answer:

    0.08382 M

    Explanation:

    Step 1: Write the balanced neutralization equation

    KHC₈H₄O₄ + KOH ⇒ K₂C₈H₄O₄+ H₂O

    Step 2: Calculate the moles corresponding to 0.4877 g of KHC₈H₄O₄

    The molar mass of KHC₈H₄O₄ is 204.22 g/mol.

    0.4877 g × 1 mol/204.22 g = 2.388 × 10⁻³ mol

    Step 3: Calculate the moles of KOH that react with 2.388 × 10⁻³ moles of KHC₈H₄O₄

    The molar ratio of KHC₈H₄O₄ to KOH is 1:1. The moles of KOH that react are 1/1 × 2.388 × 10⁻³ mol = 2.388 × 10⁻³ mol.

    Step 4: Calculate the molar concentration of KOH

    2.388 × 10⁻³ moles of KOH are in 28.49 mL of solution.

    2.388 × 10⁻³ mol / 0.02849 L = 0.08382 M

Leave an answer

Browse

Giải phương trình 1 ẩn: x + 2 - 2(x + 1) = -x . Hỏi x = ? ( )