Which one of the following involves a chemical reaction?
A. Evaporation of water
B. Storing of nitrogen gas under pressure
C. Keeping petrol in a China dish in open
D. Heating magnesium wire in the presence of air at high temperature
Answers
Answered by
5
Answer:
In the first three options, only the physical state of the water, nitrogen and petrol changes thus they are physical changes. But when magnesium wire is heated in the presence of air, formation of a new substance (MgO) takes place. The chemical reaction involved is as follows:
2Mg + O2 ——> 2MgO
Answered by
1
Answer:
option (A) evaporation of water .
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