5 2 changes of state

The three states of matter are:

True. Solids (and liquids) are not compressible.

False. Solids have a definite shape. Liquids take the shape of their container.

Liquids have no definite shape and a fixed volume.

False. Solids have a definite volume. Gases have no fixed volume.

Gases are the only state of matter that is compressible.

The properties of a solid are:

The properties of a liquid are:

The properties of a gas are:

When a liquid changes into a solid, the change of state is called freezing (or solidification).

When a liquid changes into a gas, the change of state is called boiling.

False. Condensing is when a gas changes into a liquid. When a solid turns into a liquid, the change of state is called melting.

Gases condense into liquids.

The first particle arrangement represents a solid.

The third particle arrangement represents a gas.

When a solid is heated, it melts to form a liquid.

Evaporation is the process by which a liquid is heated and changes to a gas when particles on the surface gain energy and move apart.

False. Evaporation occurs from the surface of the liquid.

The effect of heating a system will increase the energy stored within it, either raising its temperature or changing its state.

Kinetic energy in the context of particles is the energy that particles possess due to their motion.

The temperature of a material is related to the average kinetic energy of its molecules; higher temperature means higher average kinetic energy.

An increase in temperature can cause either an increase in the system's temperature or a change of state (e.g., solid to liquid, liquid to gas).

As temperature increases, the internal energy of a system also increases because the particles move faster and have more kinetic energy.

Internal energy is the total energy stored within a system, including both kinetic and potential energy of the particles.

From the bottom of the diagram to the top the internal energy increases because the particles in the gas have more kinetic energy than in a solid.

The aim of the core practical is to investigate how the temperature of ice varies when it changes state from a solid to a liquid.

True. The beaker should be about half full of ice cubes for the experiment.

The resolution of a thermometer is 0.1 °C.

A parallax error is an error in reading an instrument due to the angle of viewing, which can be avoided by keeping the instrument at eye level.

The temperature should be plotted on the y-axis of the graph.

Time should be plotted on the x-axis of the graph.

A flat region on the temperature vs. time graph indicates the change of state where ice is melting from solid to liquid.

During a change of state, thermal energy is used to weaken the bonds between particles rather than increasing their kinetic energy.

The safety equipment that should be worn while heating water is a pair of goggles.

True. The change in temperature of a substance that is heated does depend on the mass of the substance.

The temperature increase of a system depends upon:

The specific heat capacity of a substance is the amount of energy required to raise the temperature of 1 kg of the substance by 1 °C.

False. A substance with a low specific heat capacity will heat up and cool down quickly. It takes less energy to create a temperature change.

True. Different substances have different specific heat capacities.

The equation for specific heat capacity is Where:

The equation for specific heat capacity when specific heat capacity is the subject of the equation is: Where:

The aim of the experiment is to determine the specific heat capacity of a solid and of water by measuring the energy required to increase the temperature by one degree.

False. In the specific heat capacity core practical the voltmeter is connected in parallel with the immersion heater.

In the specific heat capacity core practical V represents the potential difference from the power supply.

Random errors in the specific heat capacity core practical can be minimised by stirring the water constantly and consistently choosing the higher value when current or voltage values fluctuate.

For the specific heat capacity core practical the energy supplied should be plotted on the y-axis of the graph.

Safety precautions that should be taken during the specific heat capacity core practical include: