Tag: chemistry

The more light the object absorbs, the more heat absorbed since light is energy. If you consider it a color, black absorbs the most heat. A black object absorbs all wavelengths of light and reflects none. Objects that are white, on the other hand, reflect all wavelengths of light and therefore absorb the least heat.

Conduction, convection, radiation, all the 3 processes involves heat transfer.

Convection occurs when particles with a lot of heat energy in a liquid or gas move and take the place of particles with less heat energy. Heat energy is transferred from hot places to cooler places by convection. Conduction is the transfer of energy through matter from particle to particle. 

Sublimation- It is the transition of a substance directly from the solid to the gas phase without passing through the intermediate liquid phase. 

Condensation- It is the change of the physical state of matter from gas phase into liquid phase.

Evaporation is a type of vaporization of a liquid that occurs from the surface of a liquid into a gaseous phase that is not saturated with the evaporating substance.

Deposition is a thermodynamic process, a phase transition in which gas transforms into solid.

Melting (also known as fusion) is a physical process that results in the phase transition of a substance from a solid to a liquid.

Exothermic reactions release heat and light into their surroundings. For example, combustion reactions are usually exothermic. Endothermic reactions, on the other hand, absorb heat and/or light from their surroundings. For example, decomposition reactions are usually endothermic.

When liquid changes into gas because of rise in temperature, the heat required changing the state without rising in temperature is called the Latent Heat of vaporization. The latent heat of vaporization of water is the energy which is used to change the state of water (liquid) to vapor (gas).

A liquid has a particular volume but it doesn't have a definite shape. Liquid takes the shape of the container in which it is kept.
The inter-molecular forces in case of a liquid are not as strong as in solids and hence a liquid is not held together tightly. Thus, the liquid takes up the shape of the container in which it is kept.

In a solid, the particles are held together by strong intermolecular forces between them and hence there is very little scope of movement for the particles in solid. So, kinetic energy of solid is very low.

On heating solids, intermolecular attraction between the particles decreases as the particles gain energy to move randomly.

On heating liquids, intermolecular space between molecules increases as the particles gain enough kinetic energy to overcome the force of attraction.