Why does temperature influence changes in state?

Answer 1

Solid---Liquid: When a solid heats up the particles in it vibrate more and eventually break bonds with each other, this lets them flow apart forming a liquid, however not all of the bonds completely break, so the particles still flow in one mass.This process is called melting.

Liquid---Gas: When liquid heats up the weak bonds break and the particles become free flowing with no bonds between each other, when these particles collide they do not create bonds, they bounce off each other at different angles, causing them to rise from the liquid mass. This process is called evaporation.

Gas---Liquid: As a gas cools down the particles become slower moving and have fewer collisions, however the period of contact during these collisions is much longer and they create bonds between each other. As more bonds are made the particles become heavier and fall, joining other groups of particles and bonding with them until it is one liquid mass.This process is called condensing.

Liquid---Solid: When a liquid is cooled it vibrates less and less causing the bonds between the particles to become stronger thus the solid stops flowing and becomes solid. This process is called freezing.

Solid---Gas (and vice-versa): This process is called sublimation. Some elements and compounds that sublimate include:

Carbon dioxide

Iodine