Answer:
The correct answer is a. 0.223 grams, b. 3.36 × 10²¹ and c. 2.79 × 10⁻³ mol.
Explanation:
a. The volume of the solution given is 23.46 ml or 23.46 × 10⁻³ L, the molarity of NaOH is 0.238 M or 0.238 mol/L. Now the number of moles of NaOH will be,
Number of moles = Molarity × Volume in Liters of solution
= 0.238 mol/L × 23.46 × 10⁻³ L
= 5.5835 × 10⁻³ mol
Now the mass of NaOH will be,
= Moles × Molecular mass of NaOH
= 5.5835 × 10⁻³ mol × 39.997 g/mol
= 223.322 × 10⁻³ grams
b) The number of moles in 23.46 ml is 5.5835 × 10⁻³ mol
Now the number of hydroxide ions found will be,
= No. of moles × NA
= 5.5835 × 10⁻³ × 6.022 × 10²³
= 3.36 × 10²¹
c) The balanced chemical equation is,
2NaOH + H₂SO₄ ⇒ Na₂SO₄ + 2H₂O
The number of moles of H₂SO₄ neutralized is,
= Number of moles of NaOH taken/2
= 5.5835 × 10⁻³/2 mol
= 2.7917 × 10⁻³ mol
