What happens to the pH of a hydrochloric acid solution when it is diluted with water?
Answer and explanation
Correct answer: A. It increases towards 7
- Step 1: Dilution lowers the concentration of hydrogen ions.
- Step 2: So the solution becomes less acidic and the pH rises towards 7.
Answer
It increases towards 7.
Why not the others: It decreases towards 0: dilution reduces the acidity. It stays the same: the hydrogen ion concentration drops. It increases above 7: adding water cannot make it alkaline.
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