1 |
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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2 |
What happens to water on heating. |
- A. Evaporates
- B. Condense
- C. Freez
- D. None of these
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3 |
A gas produced on heating solid potassium chlorate is. |
- A. Hydrogen
- B. Carbon dioxide
- C. Oxygen
- D. Methane
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4 |
Compustion is a. |
- A. Physical Change
- B. Chemical change
- C. Thermal change
- D. None of these
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5 |
Original colur or Nichrome wire is. |
- A. Silver grey
- B. Red hot
- C. White hot
- D. None of these
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6 |
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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7 |
What are teh products when electric current is passed through water. |
- A. Only steam
- B. Hydrogen and steam
- C. Hydrogen and oxygen
- D. Oxygen and steam
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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 |
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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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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