Boiling point is the temperature at which vapor pressure is
1. more than external pressure
2. less than external pressure
3. not related to external pressure
4. equal to external pressure
The mathematical expression that describes Boyles law is
1. PV = constant
2. V * constant = P
3. P * constant = V
4. V ? P = constant
The molecules of liquid which escape first have
1. highest kinetic energy
2. lowest kinetic energy
3.moderate kinetic energy
4. infinite kinetic energy
1 atmospheric pressure is equal to
1. 100.345 Pa
2. 760 kPa
3. 101.325 kPa
4.1.01325 mmHg
A gas that shields living things on the surface of the earth from harmful UV radiation is
1.N2
2.SO2
3.O2
4.O3
An ordered repeating three-dimensional arrangement of particles makes up a
1.crystalline solid
2.amorphous solid
3.non crystalline solid
4.none of above
As the molecular mass of gasses increases their density
1. decreases
2. increases
3. remains constant
4. none of above
At constant pressure the average kinetic energy of gas molecules increases 2 times if
1. temperature is increased by 2 times
2. temperature is halved
3. no change in temperature
4. temperature remains constant
At constant temperature when pressure is decreased the average kinetic energy of gas molecules
1.decreases
2.remains unchanged
3.decreases
4.becomes two fold
At Mount Everest the water boils at
1. 100 �C
2. 90 �C
3.80 �C
4. 70 �C
Conversion of a liquid to a gas at all temperatures is called
1. sublimation
2. evaporation
3.condensation
4. boiling
For a certain reaction PV = 2 dm3 atm and volume is 4 dm3 then the corresponding pressure is
1. 1 atm
2. 4 atm
3. 0.5 atm
4. 2 atm
Force exerted by a gas on unit area of the container is called
1.effusion
2.diffusion
3.mobility
4.pressure
If the liquid is heated to increase the kinetic energy then the liquid will
1. evaporate slowly
2. evaporate faster
3. not evaporate
4.boil
If the temperature of any gas is increased its volume
1.increases
2.decreases
3.remains same
4.none of above
In a pressure cooker the pressure applied is
1. 1 atm
2. 2 atm
3. 3 atm
4. 4 atm
In graphite the carbon atoms are arranged in layers of
1.pentagonal arrays
2.heptagonal arrays
3.octagonal arrays
4.hexagonal arrays
On applying pressure the volume of gas
1. increases
2. remains same
3.becomes double
4.decreases
On increasing the temperature of amorphous solid they
1. melt at specific temperature
2. soften gradually
3. break at specific temperature
4. boil at specific temperature
Solids whose atoms arrange themselves in different forms are
1. isotopes
2. crystals
3.allotropes
4. amorphous
The average kinetic energy of gas molecules is directly proportional to
1.T2
2.?T
3.T
4.2T
The barometer is invented by
1. Galileo
2. Robert Boyle
3. Charles
4. Torricelli
The escape of gas molecules from a small hole one after the other is called
1.diffusion
2.effusion
3.concentration
4.mobility
The melting and freezing of a substance occurs as
1. same temperature
2. more than melting point
3. more than freezing point
4. less than boiling point
The movement of molecules from higher concentration to lower concentration is called
1. diffusion
2. concentration
3. effusion
4. mobility
The position of liquid molecules are
1.fixed
2. not fixed
3. not sliding
4. none of above
The pressure that vapors apply on the surface of the liquid at equilibrium is called
1.torr
2. vapor pressure
3. liquid pressure
4. condensation
The process in which the solid changes directly into vapors without changing in the liquid state is called
1. condensation
2. evaporation
3. boiling
4. sublimation
The process in which the vapor molecules are recaptured by the molecules at the liquid surface is called
1. evaporation
2. sublimation
3. condensation
4. boiling
The temperature at which the solid starts melting is called
1. boiling point
2. freezing point
3. melting point
4. sublimating point