Question
Write the effects of chemical reactions.
✓
Answer
The effects of chemical reactions are:
1. Evolution of gas:
Gas evolution may take place as a result of chemical reactions. Example: When dilute hydrochloric acid is added to a solution of sodium carbonate or sodium bicarbonate carbon dioxide gas is evolved.
2. Change in colour:
Certain chemical changes produce change in colour. Example : When you place a iron nail in a solution of copper sulphate, the blue colour of copper sulphate slowly changes into green due to chemical reaction between iron copper sulphate solution.
3. Change in state:
Certain chemical reaction change of state is observed. Example : When you bum a piece of camphor, smoke comes out as result of chemical reaction between solid camphor and oxygen. Here, there is a change of state from solid to gas.
1. Evolution of gas:
Gas evolution may take place as a result of chemical reactions. Example: When dilute hydrochloric acid is added to a solution of sodium carbonate or sodium bicarbonate carbon dioxide gas is evolved.
2. Change in colour:
Certain chemical changes produce change in colour. Example : When you place a iron nail in a solution of copper sulphate, the blue colour of copper sulphate slowly changes into green due to chemical reaction between iron copper sulphate solution.
3. Change in state:
Certain chemical reaction change of state is observed. Example : When you bum a piece of camphor, smoke comes out as result of chemical reaction between solid camphor and oxygen. Here, there is a change of state from solid to gas.
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