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Question
A solution of a substance ‘X’ is used for white washing Name the substance ‘X’ and write its formula.
Solution
Calcium oxide CaO
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RELATED QUESTIONS
How do the following help in bringing about a chemical change?
light.
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\[\ce{KClO3 ->[heat]}\] ___________+ ____________
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In a ............ change, new substances are formed.
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| 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 |
TRUE \ FALSE
Electrolytic refining is a method in which a thin coating of a metal is done over another metal.
What are biocatalysts ?
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Melting of ice is a _______ change.
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Give an example of a reaction where the following are involved
Heat
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State the original colour of the following substance and colour of residue obtained after heating.
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