For example, when water is heated, it changes from a liquid to a gas (steam). This is because the heat energy causes the water molecules to move faster and spread out, breaking the bonds that hold them together in the liquid state. As the water molecules spread out, the water vapor becomes less dense and rises.

Another example is when sugar is dissolved in water. The sugar molecules break apart and spread out throughout the water, forming a homogeneous mixture. This is because the water molecules are able to form hydrogen bonds with the sugar molecules, which breaks the bonds between the sugar molecules and allows them to spread out.

Changes in state can also occur when matter is subjected to pressure. For example, when ice is compressed, it can be transformed into a liquid. This is because the pressure causes the ice molecules to move closer together and form stronger bonds, breaking the bonds that hold the ice molecules in the solid state.