Chemistry
A compound P is heated in a test tube with sodium hydroxide solution. A red litmus paper held at the mouth of the test tube turns blue. Which of the following could compound P be?
- zinc sulphate
- copper sulphate
- ferrous sulphate
- ammonium sulphate
Practical Chemistry
ICSE Sp 2025
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Answer
ammonium sulphate
Reason — Ammonium sulphate reacts with sodium hydroxide to produce sodium sulphate, ammonia gas, and water. The red litmus turns blue due to the basic ammonia gas.
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