If hydroxide ions are added to an acidic solution, what change will occur first?
Answer and explanation
Correct answer: Hydrogen ions will decrease by forming water
An acidic solution contains an excess of hydrogen ions, H⁺. The governing neutralisation concept is H⁺ + OH⁻ → H₂O. When hydroxide ions are added, they first consume hydrogen ions to form water, so the hydrogen-ion concentration decreases and the pH begins to rise. The solution does not instantly become solid, and neutralisation does not convert salt into metal. Therefore option A is correct.
Frequently asked questions
What is the correct answer to this question?
Hydrogen ions will decrease by forming water
Why is this the correct answer?
An acidic solution contains an excess of hydrogen ions, H⁺. The governing neutralisation concept is H⁺ + OH⁻ → H₂O. When hydroxide ions are added, they first consume hydrogen ions to form water, so the hydrogen-ion concentration decreases and the pH begins to rise. The solution does not instantly become solid, and neutralisation does not convert salt into metal. Therefore option A is 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.
