Answer to Question #119245 in Chemistry for be

Question

Calculate the quantity of H+ions present in 200 cm3 of a solution of nitric acid with a concentration of 0,25mol.dm -3

Answer 1

Solution:

Nitric acid (HNO₃) is a strong acid.

This means that HNO₃ dissociates completely to H⁺(aq) and NO₃^- (aq) when it dissolves in water.

HNO₃(aq) = H⁺(aq) + NO₃^-(aq)

Therefore,

C(HNO₃) = [H⁺] = 0.25 mol dm^-3 = 0.25 mol/L

Moles of H⁺ = [H⁺] × Volume of solution = (0.25 mol/L) × (0.2 L) = 0.05 mol

Number of H⁺ ions = Avogadro's number × Moles of H⁺

Number of H⁺ ions = 6.022×10²³ × 0.05 = 0.30×10²³ = 3.0×10²² ions

Answer: 3.0×10²² ions of H⁺.