IGCSE Chem Ch01

What is the boiling and melting point of water?

• Boiling point: 100 °C; Melting point: 25 °C
  

• Boiling point: 100 °C; Melting point: 0 °C

• Boiling point: 120 °C; Melting point: 25 °C

• Boiling point: 120 °C; Melting point: 0 °C

The kinetic theory of matter explores the spatial relationship between the particles in solids, liquids and gases.

Which of the following processes causes the distance between particles to increase by the most?

• Melting

• Freezing

• Sublimation

• Condensation

Four substance are shown below.

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

• Ice

• Air

• Steam

• Water

Which of the definition below best describe matter?

• Matter is any substance that has mass only.

• Matter is any substance that occupied space only.

• Matter is any substance that has mass and occupied space.

• Matter is any substance that has mass but cannot occupied space.

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 state 2.

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

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

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 a substance in liquid.

• The particles of solid during melting.

• A liquid being frozen.

• Diffusion of a substance through air.

What are the factors affecting the rate of diffusion?

i. temperature

ii. particle mass

iii. addition of catalyst

• i only

• i and ii only

• ii and iii only

• All of the above

Why does temperature not change during a change of state?

• Temperature will not rise, since kinetic energy of molecules remains the same.

• Temperature will not rise, since kinetic energy of molecules remains the same.

• Temperature will rise, since kinetic energy of molecules is increases.

• Temperature will rise, since kinetic energy of molecules remains the same.

Which of the following statement best describe the movement of particles in solid stage?

i. Strong forces of attraction between particles.

ii. Particles are far apart, and move quickly.

iii. Have a fixed pattern (lattice).

iv. Atoms vibrate but can’t change position therefore fixed volume and shape.

• i and ii only

• i, ii and iii only

• i, iii and iv only

• ii, iii and iv only

When the water changes into water vapor, this is called _________.

• condensation

• transpiration

• evaporation

• sublimation