| 1 |
A physical change occurs when. |
- A. Iron rusts
- B. Solution of common salt is heated
- C. A piece of wood burns
- D. Sygar us geated strongly
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| 2 |
Formation of steam from water is example of. |
- A. Chemical change
- B. Physical Change
- C. Both of these
- D. None of these
|
| 3 |
Select all that happen during a chemicla change. |
- A. A temporary chagne occurs.
- B. Composition of the substanes is changed.
- C. Propertis of the sbstances are changed.
- D. New substances with different properties are formed.
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| 4 |
Silver+ hydrogen suolphide+Oxygen--------------- Silver sulphide + water The above reaction is known as. |
- A. Combustion
- B. Rusting
- C. Tarmishing
- D. Dehydration
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| 5 |
Chemical reaction of oxygen with other substances is called. |
- A. Oxidation
- B. Reduction
- C. Rusting
- D. None of these
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| 6 |
Original colur or Nichrome wire is. |
- A. Silver grey
- B. Red hot
- C. White hot
- D. None of these
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| 7 |
Product fo combustion is. |
- A. C
- B. O2
- C. CO2
- D. All of these
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| 8 |
A piece of iron is kept in open air for 5 days. A film of corrosion formed over it is. |
- A. Iron oxide
- B. Iron sulphide
- C. Iron Chloride
- D. Iron Hydride
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| 9 |
Rusting of iron takes place in the presence of. |
- A. Moisture
- B. O2
- C. Both moisture and O2
- D. Dry air
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| 10 |
The temperature at which a liquid's vapour pressure is equal to the external pressure surrounding the liquid is. |
- A. Melting point
- B. Boiling point
- C. Freezing point
- D. Highest temperature.
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