Advertisements
Advertisements
प्रश्न
Choose the correct option from the bracket and explain the statement giving reason.
(Oxidation, displacement, electrolysis, reduction, zinc, copper, double displacement, decomposition)
To prevent rusting, a layer of ______ metal is applied on iron sheets.
उत्तर
To prevent rusting, a layer of zinc metal is applied on iron sheets.
Reason:
Zinc is a non-corrosive metal. Therefore, layer of zinc prevents rusting.
APPEARS IN
संबंधित प्रश्न
How do the following help in bringing about a chemical change?
catalyst .
MULTIPLE CHOICE QUESTIONS
Tick the most appropriate answer.
Miscible liquids having slightly different boiling points can be separated by the
- evaporation
- distillation
- fractional distillation
- sedimentation
FILL IN THE BLANK
Negatively charged ions are called ..........
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 |
TRUE \ FALSE
Copper can displace iron from iron sulphate.
How is precipitate formation in a chemical reaction indicated?
Explain the type of reactions on the basis of the direction of reaction.
State four conditions necessary for a chemical reaction to take place.
Explain the following reaction with one suitable example of Combination reactions .
Complete the statement by filling the gaps using appropriate term from the terms given in the bracket.
(slow, coloured, arrow, fast, smell, milky, physical, product, chemical, reactant, covalent, ionic, octet, duplet, exchange, sharing, equality sign)
The white particles of baking soda disappear when put in lemon juice. This means that it is a ______ change.
Show with the help of diagram of electronic configuration how the following compound is formed from the constituent atoms.
Potassium fluoride
State the original colour of the following substance and colour of residue obtained after heating.
Copper carbonate
Distinguish by heating the following in dry test tubs.
Copper Sulphate and copper carbonate
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Zinc carbonate.
Name the solid residual product formed reaction and state its colour during – thermal decomposition of the following substance.
Calcium hydroxide.
Photosynthesis is a chemical reaction that takes place in the presence of ______.
A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
What changes do you expect?
A student took a solution of copper sulphate in a beaker and put a clean iron nail into it and left it for about an hour.
Are these changes chemical in nature?
Galvanization is a process in which ______ is coated as a layer of iron.
The reaction of H2 gas with oxygen gas to form water is an example of ______.
