A solid block of a substance is heated. Thermal energy is supplied to the solid by a heater. The temperature of the solid increases until it reaches its melting point. The solid then starts to melt and change into a liquid.
Describe, in terms of molecules and their arrangement or motion, how a solid differs from a liquid.
Describe what happens to the molecules of the solid as its temperature begins to increase.
Explain, in terms of molecules, why a supply of thermal energy is needed to change the solid into a liquid at its melting point.
The density of the solid is 1.25 g/cm31.25\text{ g/cm}^31.25 g/cm3. The volume of the solid block is 80 cm380\text{ cm}^380 cm3.
The solid reaches its melting point. It now absorbs 34000 J34000\text{ J}34000 J of thermal energy and all of the solid changes into a liquid.
Calculate the specific latent heat of fusion of this substance.
specific latent heat of fusion=……………………………… \text{specific latent heat of fusion} = \dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots\dots specific latent heat of fusion=………………………………313 exam-style questions on CIE IGCSE Physics 2.2.3a Melting, boiling, condensation and solidification. Each one has a worked solution and a mark scheme showing where the marks go.