States of Matter

 factual

Fluids don’t have a definite shape. They take the shape of the container.

Liquefaction, sometimes liquification, refers to any process which either generates a liquid from a solid or a gas, or generates a non-liquid phase which behaves in accordance with fluid dynamics

With change in temperature matter changes its phase

Freezing is a phase transition in which a liquid turns into a solid when its temperature is lowered to its freezing point

Condensation is the change of water from its gaseous form (water vapor) into liquid water. Condensation generally occurs in the atmosphere when warm air rises, cools and loses its capacity to hold water vapor. As a result, excess water vapor condenses to form cloud droplets.

Due to the slippery nature of any two layers of graphite, it is used as a lubricant.

Correct answer is option (3).

Iodine and alcohol form a solid-liquid homogeneous mixture.

The substance which is dissolved in a liquid to make a solution is called solute.

People sprinkle water on the roof or a hot surface because the large latent heat of vaporisation of water helps cool the hot surface.  Latent heat of fusion is the amount of heat energy required to convert 1 kg of solid into liquid at its melting point. Sublimation is the phenomenon of direct conversion of a solid into the gaseous state on heating and vice-versa on cooling without passing through the intervening liquid state. Precipitation involves formation of insoluble products. Thus, these options are incorrect.

Melting is the process of conversion of solid to liquid and the amount of heat energy required to convert 1 kg of solid to liquid at atmospheric pressure at its melting point is called latent heat of fusion. When ice at 0^oC melts to form water at 0^oC, it absorbs extra heat in the form of latent heat of fusion, i.e. water at 0^oC has more heat than ice and therefore, ice at 0^oC is more effective in cooling than water at 0^oC. During melting, heat is absorbed and not released because heat is required to overcome the forces of attraction so as to convert solid to liquid. Therefore, option (4) is incorrect. Evaporation is the conversion of liquid to vapours at temperature below its boiling point. Hence, options (1) and (2) are incorrect.

When heat is supplied to a crystalline solid, its temperature increases and hence, kinetic energy of the constituent particles increases. Due to increase in kinetic energy, the particles start vibrating with greater speed. As the temperature is further increased, the energy supplied in the form of heat overcomes the forces of attraction between the particles. At this stage, the particles leave their fixed position and start melting to become liquid. Once the solid starts melting, the temperature of the substance does not rise during the change of state. This is because the heat being supplied is used up in overcoming the forces of attraction between the particles of a solid during the change of state from solid to liquid. Therefore, temperature of the substance remains the same when solid melts to become liquid. The heat is believed to be hidden within the particles and is called latent heat.

Ice formed at the surface of water bodies protects the water beneath from the cold air above. Thus, the warmth of water below the layer of ice is preserved and not dissipated to the atmosphere.

Ramesh’s beaker will be heated earlier because the outermost part of the flame is the hottest zone.