Properties of Liquid (Old NCERT) - Free MCQ Practice Test with solutions,

Because in a closed vessel the amount of liquid is constant i.e the water which is converted into vapour again condenses to form water and boiling occurs when vapour pressure is equal to atmospheric pressure since it is closed so they couldn't be equal.

At higher altitudes, air pressure is lower. When atmospheric pressure is lower, such as at a higher altitude, it takes less energy to bring water to the boiling point. Less energy means less heat, which means water will boil at a lower temperature at a higher altitude.

Vapor pressure is an intensive property, since it only depends on the fraction of the surface particles that can vaporize.

The vapour pressure of a liquid depends only on the nature of the liquid and the temperature. It does not depend on the volume of the container so it is 20.0mm.

SURFACE TENSION:
Surface Tension is a property of liquid at rest by virtue of which a liquid surface gets contracted to a minimum area and behaves like a stretched membrane.
An increase in temperature of water (or any liquid) leads to an increase in kinetic energy of molecules. Thus, intermolecular forces among molecules are lowered and a decrease in surface tension is noticed.

The cohesive forces between liquid molecules is responsible for the surface tension. The molecules of water on the surface don't have like molecules around it.So the water droplets tend to be pulled into shape of spherical due to cohesive forces.Thats why, the drop of water is always spherical.

This is the SI unit of viscosity, equivalent to newton-second per square metre (N. s m^-2). It is sometimes referred to as the poiseuille (symbol Pl). One poise is exactly 0.1 Pa

Vapour density is equal to molecular mass by 2 therefore the molecular mass of the gas will be 32 so we have a diatomic elementary gas so atomic mass will be molecular mass divided by two of the atomic mass of the gas will be 16.

Viscosity is the measure of resistance of a fluid to flow. A fluid that is highly viscous has a high resistance (like having more friction) and flows slower than a low-viscosity fluid. As Honey would move slower than water, so honey would have a greater viscosity.

The vapor pressure of a liquid is the equilibrium pressure of vapor above the liquid at a given temperature. Thus, all else (molar mass, for example) equal, a polar molecule will generally have a lower vapor pressure than a non-polar molecule.

Surface tension depends on the attractive forces acting b/w molecules. 
S = F/l

The amount of water vapor in the air also affects the density. Water vapor is a relatively light gas when compared to diatomic Oxygen and diatomic Nitrogen. Thus, when water vapor increases, the amount of Oxygen and Nitrogen decrease per unit volume and thus density decreases because mass is decreasing.

Glycerol
The reason behind is that it is a viscous liquid.

Number of moles when condition of STP is given by given volume divided by 22400 this will give number of moles and after that number of moles X molecular mass will give the mass of the given sample.

Viscosity is simply the frictional force that arises between adjacent layers of fluid that are in relative motion. Viscosity is a measurement of how resistant a fluid is to attempts to move through it.

Graham's law states that the rate of diffusion or effusion of a gas is inversely proportional to the square root of its molar mass. r ∝ 1/√M.
In option A, all the compounds have the same mass(44g).

Vapour pressure is the only property which decreases with increase in temperature. A pure liquid experiences a greater amount of vapour pressure as against a liquid's solution. It is inversely proportional to the forces of attraction existing between the molecules of a liquid. It increases with a rise in the temperature. This is because the molecules gain kinetic energy and thus, vapourise briskly. On the other hand, with increase in kinetic energy of molecules, Viscosity and surface tension decreases.

S = F/l
So the SI unit of surface tension is Nm^-1

Vapour pressure will be the same because it doesn't depend on the volume. It depends only on temperature.

Boiling is the free vaporisation throughout the liquid. Every molecule of the sample has the same kinetic energy to dissociate from the liquid state. So this will result in free vapourisation.On the other hand, evaporation is restricted vaporisation throughout the liquid. As the molecules present on the surface only vaporises.