Rate of evaporation of petrol is greater than that of water at room temperature because:

A. Petrol molecules do not have any hydrogen bond
B. Petrol is an organic compound
C. Water molecules have small size
D. Petrol molecules have greater size

The increasing vapor pressure caused by heating a liquid is due to___________?

A. Increase inter-molecular interactions
B. Increasing potential energy of molecules
C. Increasing kinetic energy of molecules
D. Decreasing surface tension

All of the following substances are crystalline except_____________?

A. Ice
B. Diamond
C. Sucrose
D. Plastic

An atom is_____________?

A. Smallest indivisible particle in an element
B. Smallest particle of an element which can undergo a chemical reaction
C. Building block of an element
D. Always smaller than molecule

Which of the following is a substance?

A. Sea water
B. Brass
C. Tape water
D. Graphite

The average speed of a moving object during a given interval of time is always:

A. The magnitude of its average velocity over the interval
B. The distance covered during the time interval divided by the time interval
C. One-half its speed at the end of the interval
D. Its acceleration multiplied by the time interval

Which of the following is closest to a yard in length?

A. 0.01m
B. 0.1m
C. 1m
D. 10m

During a total solar eclipse the rate of Photosynthesis___________?

A. Increase
B. Decrease
C. Remain constant
D. None of them

Water is a universal solvent for what reactions?

A. Chemical
B. Biochemical
C. Physical
D. Nuclear

The SI standard of time is based on_____________?

A. the daily rotation of the earth
B. the frequency of light emitted by kr86
C. the yearly revolution of the earth about the sun
D. a precision pendulum clock