Science
A student performs the following experiment in his school laboratory.
List two observations to justify that in this experiment a chemical change has taken place.
Metals & Non-Metals
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Answer
When zinc granules react with dilute sulphuric acid, a chemical change takes place.
Two observations that justify this are :
- Effervescence (bubbling) is observed, indicating that a gas (hydrogen) is being evolved.
- The zinc granules gradually dissolve / become smaller and the flask becomes warm, showing that a new substance is formed and heat is produced.
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