chem unit test review

Which statement describes a limitation of the kinetic-molecular theory for a gas? The theory assumes that particles do not experience intermolecular forces. The theory states that pressure is inversely proportional to volume. The theory assumes that particles are in random and continuous motion. The theory states that pressure increases with temperature.

The theory assumes that particles do not experience intermolecular forces.

Which statement describes an extensive property of matter? It changes with the color of a substance. It changes when a new substance is formed. It changes with the amount of sample that is present. It changes with the composition of a substance.

It changes with the amount of sample that is present.

The diagram below shows the different phase transitions that occur in matter.Which best describes the process that arrow 1 represents? Molecules are speeding up during boiling. Molecules are depositing as ice on a surface. Molecules are slowing down during condensing. Molecules are moving from stationary positions.

Molecules are speeding up during boiling.

Which best characterizes a crystal? a number of high speed particles moving randomly a dense substance that is hard and incompressible a high-energy state of matter made up of a swirling, ionized gas a loose association of particles moving past one another

a dense substance that is hard and incompressible

Consider the temperature versus time graph below.At what temperature is the substance a heated gas? at 100°C below 0°C above 100°C between 0°C and 100°C

above 100°C

When a strip of magnesium metal is touched to a flame, a bright light and a whitish substance are produced. Why is the burning of magnesium considered a chemical change? because the metal reaches a high temperature because the metal begins to melt because a new substance is formed because the metal is malleable

because a new substance is formed

A gaseous substance turns directly into a solid. Which term describes this change? deposition evaporation melting sublimation

deposition

In the diagram below, particles of the substance are moving from the liquid phase to the gas phase at the same rate as they move from the gas phase to the liquid phase.The gas and liquid are at... equilibrium. a high vapor pressure. a low vapor pressure. zero vapor pressure.

equilibrium.

When the process of condensation occurs, the kinetic energy of particles... is insufficient to overcome intermolecular forces. becomes independent of temperature. becomes exactly equal to the intermolecular forces. easily overcomes the intermolecular forces.

is insufficient to overcome intermolecular forces.

Which sequence represents the relationship between pressure and volume of an ideal gas as explained by the kinetic-molecular theory? more gas particles more collisions higher pressure smaller volume crowded particles less collisions lower pressure smaller volume crowded particles more collisions higher pressure more gas particles more kinetic energy more volume higher pressure

smaller volume crowded particles more collisions higher pressure

Which statement best compares the melting point of butane (C4H10) with that of octane (C8H18)? The melting points of both substances are identical. The melting point is higher for butane. The melting point is higher for octane. The comparison of melting points cannot be made.

The melting point is higher for octane.

Which best explains why water has a much higher boiling point than would otherwise be predicted? Water forms weak hydrogen bonds. Water forms strong hydrogen bonds. Water has weak cohesive forces. Water has strong adhesive forces.

Water forms strong hydrogen bonds.

Which of these is an example of a physical change? sugar, when heated, producing carbon dioxide and water solid ice, when heated, turning into liquid water sodium, when exposed to chlorine, forming sodium chloride aluminum, when heated in air, forming aluminum oxide

solid ice, when heated, turning into liquid water

The diagrams show the particles of a substance.Which statement best describes the process that the diagrams show? A solid loses kinetic energy to become a liquid and then becomes a gas. A solid gains kinetic energy to become a liquid and then becomes a gas. A gas loses kinetic energy to become a liquid and then becomes a solid. A gas gains kinetic energy to become a liquid and then becomes a solid.

A solid gains kinetic energy to become a liquid and then becomes a gas.

Which is a postulate of the kinetic-molecular theory? Gas particles have a small volume relative to the spaces between them. Gas particles have a large volume relative to the spaces between them. Gas particles are very small in size and always move slowly. Gas particles are very large in size and always move slowly.

Gas particles have a small volume relative to the spaces between them.