Practice question
Question
The Ksp of CuS is 6.3 × 10⁻³⁶ . What is the pH at which [Cu²⁺] = 1.0 × 10⁻¹² M in a saturated solution, given Ka of H₂S = 9.5 × 10⁻⁸ and Ka₂ = 1.0 × 10⁻¹⁹ ?
Explanation
For CuS <=> Cu²⁺ + S²⁻ , Ksp = [Cu²⁺][S²⁻] = 6.3 × 10⁻³⁶ , [S²⁻] = 6.3 × 10⁻²⁴ . For H₂S <=> 2H+ + S²⁻ , K = Ka₁ × Ka₂ = 9.5 × 10⁻²⁷ , [S²⁻] = (K [H₂S]/[H+]²) , assume [H₂S] = 0.1 M , 6.3 × 10⁻²⁴ = (9.5 × 10⁻²⁷ × 0.1/[H+]²) , [H+]² = 1.51 × 10⁻⁴ , [H+] = 1.23 × 10⁻² , pH ≈ 1.91 .
Related blogs
Guides and insights connected to this topic
SARS-CoV-2 Coronavirus: Structure, Genome, Proteins, Replication, Pathogenesis, and Host Interaction
Coronavirus Overview Coronaviruses (CoVs) are enveloped viruses (surrounded by a lipid membrane derived from host cells), belonging to the s...
Cucumber Mosaic Virus (CMV): Structure, Genome, Symptoms, Disease Cycle and Management
Cucumber Mosaic Virus (CMV): Introduction and Importance Cucumber Mosaic Virus (CMV) (plant-infecting RNA virus) is one of the most economic...
Human Astrovirus- An Introduction
Structure of Human Astrovirus Human astrovirus (virus causing gastroenteritis in humans) falls under Astroviridae (virus family) and genus M...