Let's return to the melting glacier from the start of the lesson.Using the particle model, explain why the solid ice melts as the temperature increases.

The particle model of matter states that all matter is made up of tiny particles which are constantly moving. The speed of these particles depends on their energy, which is directly related to the temperature of the substance.

In the case of a glacier, the ice is in a solid state, meaning its particles are closely packed together and vibrate in fixed positions. They have low energy due to the cold temperature.

As the temperature increases, the particles gain more energy. This energy makes the particles vibrate faster.

Eventually, the particles gain enough energy to overcome the forces holding them in their fixed positions. This allows them to start moving more freely.

This change in particle movement marks the transition from a solid state (ice) to a liquid state (water). This process is what we refer to as melting.

Therefore, as the temperature of the glacier increases, the ice melts because the increased energy allows the particles to move from a fixed position (solid state) to a more free movement (liquid state).