What is being taught lesson by lesson:
- Introduction to particle theory. We will find out what you already know and address any misconceptions you may have picked up.
- Measuring the density of regular solid objects
- Calculation of results followed by finding out the density of irregular objects using Archimedes’ principle.
- Differences between physical and chemical changes.
- The internal energy of particles in a closed system.
- Mars colony problem solving.
- The Specific Heat capacity of substances. Measuring and calculating.
- Specific latent heat.
- Particle motion in gases. Calculations using PV=constant.
Key Terms for this topic (Tier 3 vocabulary)
Density – matter – displacement – internal energy – latent heat.
What everyone needs to know:
Density is the mass of an object divided by its volume. The volume can be calculated or for an irregular shape, measured using a displacement can or a measuring cylinder.
List all of the potential changes of state and the names of the process of changing between them (boiling, freezing etc.) Internal energy is a measure of the kinetic energy of the particles within a substance, when it is heated, the internal energy of the substance increases until it changes state.
Measuring the change in energy is done by referring to the specific heat capacity: ΔE = m c ΔΘ
Change in energy = mass x specific heat capacity x change in temperature.
Energy is needed to “rearrange” the particles in a substance when it changes state, this energy is called the Specific Latent Heat. When changing state, the temperature does not change. E=mL
Energy = mass x specific latent heat.
Finally, describe the random motion of particles in a gas. By changing the temperature at a constant volume will increase the pressure. You must be able to link this relationship and describe how one thing causes the other.
Required practical 17 – Measure the density of an object with an irregular shape. Use appropriate equipment and measurements.
Extra topics needed for the Higher papers:
In this topic, there is nothing extra for the higher papers, the questions will just be more challenging.