Physical Chemistry Answers

Which of these is not true of a lattice?
It resembles a scaffold erected for the construction of a building
Lattice is present only in ionic solids
It is an arrangement of geometrical points in a definite pattern in space
A regular periodic arrangement of points in space

Which of the followings does not influence the magnitude of surface tension?
Metallic bonding
Hydrogen bonds
Ionic bonding
Dispersion forces
Question 20 : Which one of the following statements is not consistent with the kinetic-molecular theory of gases?
Individual gas molecules are relatively far apart.
There is no net gain or loss of the total kinetic (translational) energy in collisions between gas molecules.
The actual volume of the gas molecules themselves is very small compared to the volume occupied by the gas at ordinary temperatures and pressures.
The average kinetic energies of different gases are different at the same temperature.

In 5 sec.80% of reaction is complete. If reaction is 1st order then calculate rate constant.

16 One mole of an ideal gas is heated at a constant pressure of 101300 N
$m^{2}$, from 273.2 K to 373 K. Calculate the work involved R = 8.314

Question 17 : Which statement is false?
Gases can be expanded without limit.
The density of a gas is constant as long as its temperature remains constant.
The molecular weight of a gaseous compound is a non-variable quantity.
Gases diffuse into each other and mix almost immediately when put into the same container.
Question 18 : A separation technique which involves charging particles and then attracting them to oppositely charged metal plates is called _____ separation.
gravity
electrostatic
magnetic
absorption
Question 19 : Which of these is a derived physical quantity?
Time
Mass
Area
Luminous intensity
Question 20 : Which of these terms is not used to describe a solid which remains behind during a separation process?
sediment
filtrate
solution
residue

Question 4 : In order to dissolve the greatest amount of sugar in a cup of water, you should __________.
use sugar in large pieces, and cool the water
use sugar crushed into small pieces, and cool the water
use sugar crushed into small pieces, and heat the water
use sugar in large pieces, and heat the water

Question 6 : Which of the following is not true of a liquid’s viscosity?
It increases with temperature
It is a measure of the resistance to flow
A highly viscous liquid flows slowly
It is independent on intermolecular forces
Question 7 : A sample of an ideal gas is held at constant temperature. If the pressure is decreased to ½ P, the volume will be _________.
reduced in multiples of two
Decreased to ½ V
Unchanged
Increased to 2V

Question 1 : Which of these is not true about semiconductors?
They are insulators under normal conditions
Electrical conductivity increases with temperature
They conduct when heated
They conduct under normal conditions
Question 2 : Which of the following is a pure substance made up of one type of atoms?
A solution
A mixture
A compound
An element
Question 3 : Which of the following is not a colligative property?
Increase in latent heat
Boiling point elevation
Freezing point depression
Vapour pressure lowering

Question 6 : A sample of nitrogen occupies 5.50 liters under a pressure of 900 torr at 25oC. At what temperature will it occupy 10.0 liters at the same pressure?
154 oC
−109oC
269 oC
32 oC
Question 7 : A sample of an ideal gas is held at constant temperature. If the pressure is decreased to ½ P, the volume will be _________.
reduced in multiples of two
Increased to 2V
Unchanged
Decreased to ½ V
Question 8 : Which of these is a derived physical quantity?
Time
Luminous intensity
Mass
Area
Question 9 : In order to dissolve the greatest amount of sugar in a cup of water, you should __________.
use sugar crushed into small pieces, and heat the water
use sugar in large pieces, and heat the water
use sugar in large pieces, and cool the water
use sugar crushed into small pieces, and cool the water
Question 10 : The kinetic energy of gas molecules is directly proportional to temperature in ___________.
none of these
Kelvin
Celcius
degree kelvin

Question 11 : Which of these is not true of a lattice?
It resembles a scaffold erected for the construction of a building
Lattice is present only in ionic solids
It is an arrangement of geometrical points in a definite pattern in space
A regular periodic arrangement of points in space
Question 12 : Which of the following is not a colligative property?
Increase in latent heat
Boiling point elevation
Freezing point depression
Vapour pressure lowering
Question 13 : A sample of a salt and water solution is homogeneous throughout. Is this sample a mixture or a pure substance?
a mixture, because it has a fixed, definite composition
a mixture, because it can have a variable composition
a pure substance, because it has a definite composition
a pure substance, since it is the same throughout

Question 8 : Which of these is a derived physical quantity?
Time
Luminous intensity
Mass
Area
Question 9 : In order to dissolve the greatest amount of sugar in a cup of water, you should __________.
use sugar crushed into small pieces, and heat the water
use sugar in large pieces, and heat the water
use sugar in large pieces, and cool the water
use sugar crushed into small pieces, and cool the water
Question 10 : The kinetic energy of gas molecules is directly proportional to temperature in ___________.
none of these
Kelvin
Celcius
degree kelvin