If two acidic solutions have pH values 2 and 4 respectively, which one has a higher concentration of hydrogen ions?
Answer and explanation
Correct answer: Solution with pH 2
The governing relation is pH = −log₁₀[H⁺], so [H⁺] = 10⁻ᵖᴴ. For pH 2, the hydrogen-ion concentration is 10⁻² mol/L; for pH 4, it is 10⁻⁴ mol/L. The ratio is 10⁻² ÷ 10⁻⁴ = 10² = 100. Thus, the pH 2 solution has 100 times the hydrogen-ion concentration of the pH 4 solution, making option A correct.
Frequently asked questions
What is the correct answer to this question?
Solution with pH 2
Why is this the correct answer?
The governing relation is pH = −log₁₀[H⁺], so [H⁺] = 10⁻ᵖᴴ. For pH 2, the hydrogen-ion concentration is 10⁻² mol/L; for pH 4, it is 10⁻⁴ mol/L. The ratio is 10⁻² ÷ 10⁻⁴ = 10² = 100. Thus, the pH 2 solution has 100 times the hydrogen-ion concentration of the pH 4 solution, making option A correct.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Acids, Bases, and Salts.
