Chapter 1 States of matter

Many chemical processes involve substances in either the liquid or the gaseous state.

Which of the following statements is correct?

• A specific mass of a gas has a fixed volume at room temperature

• A specific mass of a liquid has a fixed volume at room temperature

• 25 cm³ of gas contains more particles than 25 cm³ of liquid

• Liquid particles placed inside a sealed container have fixed positions

Four substances are shown below.

In which of these substances are the particles close together and moving slowly past each other?

• Ice

• Air

• Steam

• Water

A student noted the following observation in his laboratory notebook:

“The particles moved slowly from an area of high concentration to an area of low concentration.”

Which process is being described?

• Diffusion of substance in a liquid.

• The particles of a solid during melting.

• A liquid being frozen.

• Diffusion of a substance through air.

A small amount of bleach was accidentally spilled on a kitchen floor.

After a while it was observed that the floor appeared to be dry and the whole kitchen smelled of bleach.

Which processes have occurred?

• Evaporation and diffusion

• Distillation and diffusion

• Evaporation only

• Diffusion only

Which words complete the gaps 1 & 2 in these sentences?

As the temperature of air in a balloon ............1.............. the volume increases.

When the volume of air in a balloon increases the pressure ...............2...................

• A

• B

• C

• D

The following four statements describe the arrangement of particles in a substance.

Which of the four statements describe the arrangement of particles in a solid?

• 1 and 2

• 2 and 4

• 1 and 3

• 2 only

The diagram shows a cup of hot chocolate which was prepared by mixing boiling water with chocolate powder.

Which row correctly describes the particles of water in the air above the cup compared to those in the hot chocolate drink inside the cup?

• Particles move faster, Particles are closer together

• Particles move faster, Particles are not closer together

• Particles do not move faster, Particles are closer together

• Particles do not move faster, Particles are not closer together

The diagram shows what happens when a blue soluble crystal is placed in a beaker of water.

Which row correctly describes the processes taking place?

• Chemical process, Dissolving, Diffusion

• No chemical process, No dissolving, Diffusion

• Chemical process, No dissolving, Diffusion

• No chemical process, Dissolving, Diffusion

Substance X can occur in three different physical states as shown in the diagram.

Which statement is correct?

• In state 1 the particles vibrate around fixed positions but don't move.

• Diffusion occurs in the phase change from state 1 to 2.

• The volume of the substance in state 3 is fixed.

• Condensation occurs in the phase change from state 3 to 2.

Matter exists in three states which are solid, liquid and gas. Phase changes occur when matter changes from one state to another.

In which changes do the particles move closer together?

• 1 and 2

• 1 and 3

• 3 and 4

• 4 only