Which of the following changes is an indication of a chemical reaction?
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Answer and explanation
Correct answer: Rusting of iron
When iron rusts, it reacts with oxygen and moisture to form a new substance, hydrated iron oxide (rust). Therefore, rusting is a chemical change. In contrast, boiling water and melting wax are only changes of state, while dissolved salt can be recovered from water by evaporation.
Frequently asked questions
What is the correct answer to this question?
Rusting of iron
Why is this the correct answer?
When iron rusts, it reacts with oxygen and moisture to form a new substance, hydrated iron oxide (rust). Therefore, rusting is a chemical change. In contrast, boiling water and melting wax are only changes of state, while dissolved salt can be recovered from water by evaporation.
Which subject and chapter does this question cover?
This is a Class 10 Science question. Chapter: Chemical Substances – Nature and Behaviour. Topic: Chemical Reactions and Equations.
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