Answer:
2.03 × 10⁻⁵ M
Explanation:
Step 1: Given data
Concentration of Pb(NO₃)₂: 6.73 ppm = 6.73 mg/L
Step 2: Convert 6.73 mg/L to mol/L
The molar mass of 331.2 g/mol.
6.73 × 10⁻³ g/L × 1 mol/331.2 g = 2.03 × 10⁻⁵ mol/L = 2.03 × 10⁻⁵ M
Step 3: Calculate the molar concentration of Pb²⁺
Let's consider the ionization of Pb(NO₃)₂.
Pb(NO₃)₂(aq) ⇒ Pb²⁺(aq) + 2 NO₃⁻(aq)
The molar ratio of Pb(NO₃)₂ to Pb²⁺ is 1:1. The molar concentration of Pb²⁺ is 1/1 × 2.03 × 10⁻⁵ M = 2.03 × 10⁻⁵ M.