What is the difference between a solid and a liquid in terms of particle arrangement?
Solids have closely packed particles in a regular arrangement, while liquids have particles close
together but can move past each other.
How is density calculated?
Density = mass ÷ volume
A block has a mass of 2 kg and a volume of 0.001m³. Calculate its density. (Ρ = m/V)
2 ÷ 0.001 = 2000 kg/m³
Name the state change when a gas turns into a liquid.
Condensation.
What happens to the particles when a substance melts?
Particles gain energy, vibrate more, and move past each other, changing from a solid to a liquid.
Name the state change when a solid turns directly into a gas
Sublimation.
A 200 g metal block is heated from 20°C to 70°C, absorbing 8,000 J. Calculate its specific heat capacity. 𝑐=𝐸÷(𝑚Δ𝜃)
8000 ÷ (0.2 × 50) = 800 J/kg°C
What is internal energy?
The total energy stored by particles in a system.
(Kinetic energy + potential energy)
Why does increasing temperature increase the pressure of a gas in a fixed container?
Particles move faster, collide more frequently and with more force on the walls.
Explain why solids have a fixed shape.
Particles are in a fixed, regular arrangement and vibrate but do not move past each other.
A 50 g ice cube absorbs 10,500 J to melt. What is the specific latent heat of fusion of ice? 𝐿=𝐸÷𝑚
10500 ÷ 0.05 = 210,000 J/kg
What is specific heat capacity?
The energy needed to raise the temperature of 1kg of a substance by 1°C.
What piece of equipment can be used to find the volume of an irregular shaped object?
Eureka can / measuring cylinder.
Explain the difference between specific heat capacity and latent heat.
Specific heat capacity relates to temperature change; latent heat relates to state change at
constant temperature.
0.1 kg of steam condenses into water. The latent heat of vaporisation of water is 2.26 × 10⁶ J/kg. How much energy is released? 𝐸=𝑚𝐿
0.1 × (2.26 × 10⁶) = 2.26 × 10⁵ J.
