Question

Which substance among those mentioned below sublimes in open air ?
a) Sugar
b) Paraffin
c) Sodium chloride
d) Solid carbon dioxide.
f water kent in air is measured simultaneous)​

Answer 1

Which substance give heat and light after combustion
a. Flame
b. Fuel
c. Combustion
d. None of these
2. Like fuel the sun also provides heat and light. The process taking place in the sun is called
a. Combustion
b. Nuclear process
c. Burning
d. All of these
3. Coal burns with ______
a. Flame
b. Only glow
c. Both flame and glow
d. None of these
4. Burning of charcoal in a closed room will produce
a. Carbon dioxide
b. Nitrogen dioxide
c. Carbon monoxide
d. All of these
5. The substances which have very low ignition temperature will
a. Catch fire easily
b. Will not catch fire
c. Catch fire after some time
d. None of these
6. CNG and LPG are the examples of
a. Solid fuels
b. Liquid fuels
c. Gaseous fuels
d. They are not fuels
7. Ignition temperature is
a. Lowest temperature at catch fire
b. Higher temperature at catch fire
c. Any temperature
d. None of these
8. Combustion is a
a. Chemical process
b. Physical process
c. Both of these processes
d. None of these processes
9. The products of combustion are
a. Carbon dioxide and water
b. Oxygen and water
c. Only carbon dioxide
d. Only oxygen
10. There are following zones of a flame
a. Two
b. Three
c. Four
d. No any zone
ANSWERS
1. B
2. B
3. B
4. C
5. A
6. C
7. A
8. A
9. A
10. B