What happens to the pH value when the concentration of hydrogen ions increases in an acidic solution?
Answer and explanation
Correct answer: pH decreases
The governing relationship is pH = −log[H⁺]. Because the logarithm is preceded by a minus sign, increasing the hydrogen-ion concentration makes the pH value decrease. Therefore option B is correct. A lower pH indicates a more acidic solution. The value does not automatically become 7, since pH 7 represents neutrality at standard conditions, and it cannot remain unchanged when [H⁺] changes.
Frequently asked questions
What is the correct answer to this question?
pH decreases
Why is this the correct answer?
The governing relationship is pH = −log[H⁺]. Because the logarithm is preceded by a minus sign, increasing the hydrogen-ion concentration makes the pH value decrease. Therefore option B is correct. A lower pH indicates a more acidic solution. The value does not automatically become 7, since pH 7 represents neutrality at standard conditions, and it cannot remain unchanged when [H⁺] changes.
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.
