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प्रश्न
State four conditions necessary for a chemical reaction to take place.
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उत्तर
Ans: Close contact— For a chemical reaction to take place the reactants should be brought in close contact i.e., they should be mixed,
\[\ce{Sodium + Water -> Sodium hydroxide + Water}\]
Solution form— Some substances react with each other only when they are mixed in the solution form, e.g.,
\[\ce{\underset{\text{(aq.)}}{Silver nitrate} + \underset{\text{(aq.)}}{Sodium chloride} ->\underset{\text{(ppt.)}}{Silver nitrate}+\underset{\text{(aq.)}}{Sodium nitrate}}\]
Heat— Some reactants need to be heated to undergo a chemical change, e.g.,
\[\ce{Potassium chlorate->[heat] Potassium chloride + oxygen}\]
Light— Some reactions take place in the presence of light.
\[\ce{Carbon dioxide + Water ->[chlrophyll][sunlight] Glucose + Oxygen}\]
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संबंधित प्रश्न
Complete and balance the following chemical equations:
N2 + O2 →
MATCH THE COLUMNS
| 1 . `H_2` + `CI_2` `→` 2HCI | a. displacement reaction |
| 2. `2FeCI_3`+ `H_2` `→` `2FeCI_2` +2HCI` | b. addition of an electronegative redical |
| 3. Fe + `CuSO_4` `→``FeSO_4` +Cu` | c. removal of an electronegative redical |
| 4. `2H_2O` +`4NO_2`+`O_2` `→` `4HNO_3` | d.reduction by adding hydrogen |
| 5. 3Fe +`3CI_2` `→` `2FeCI_3` | e.electrolysis of water |
| 6. `FeCI_3`+ 3NaOH `→``Fe(OH)_3``↓`+NaCI | F.double decomposition,precipitation reaction |
| 7.`2H_2O` `→` `2H_2``↑`+`O_2` | e. combination or synthesis reaction |
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