States of Matter Quiz

Explain why dew forms on cool mornings.

When water vapor in the air comes in contact with a cool object such as a windshield, it condenses on the object.

Use Kinetic Theory to explain the behavior of gases.

- All matter is made of tiny particles in constant motion. - The average kinetic energy of the gas particles is directly proportional to the temperature of the gas. - The volume of the particle is smaller compared to the distance between the particles (volume). - The pressure of gas is created by the collision of the particles with their surroundings.

Three Basic assumptions of the Kinetic Theory

1.Matter is composed of small particles. 2.The particles are in constant motion and undergo elastic collisions. 3. The particles have kinetic energy and the average kinetic energy of the particles is temperature.

1 atm:

760 mmHg, 760 torr, 101.3 kPa, 14.7 psi

the difference between a molecular solid and a covalent network solid?

A molecular solid is formed from molecules held together by intermolecular forces that are weaker than covalent bonds; covalent network solids are formed from molecules held together by strong covalent bonds.

Compare deposition and sublimation

A substance undergoes deposition when it goes from the vapor phase to the solid phase without going through the liquid phase. A substance undergoes sublimation when it goes from the solid phase directly to the vapor phase without going through the liquid phase. Both occur at the same temperature for a given substance.

How does the kinetic energy of particles vary as a function of temperature?

As the temp increases, the average kinetic energy of the particles also increase.

Use the kinetic-molecular theory to explain the compression and expansion of gases.

Because of the space between gas particles, gases are easily compressed when pushed into a smaller volume. When the pressure is removed, their random motion enables gases to expand.

Explain the relationships among vapor pressure, atmospheric pressure, and boiling point.

Boiling point is the temperature at which vapor pressure exerted by liquid molecules escaping from the surface of a sample equals the atmospheric pressure on the surface of the liquid.

The difference between the processes of melting and freezing?

Freezing occurs when a liquid becomes a solid and energy is released. Melting requires an input of energy to convert a solid to a liquid.

Difference between arrangement of particles in a solid vs. liquid

In both, particles are arranged compactly. But in a solid, particles vibrate in place, while in a liquid they freely move around.

Difference between intermolecular and intramolecular forces?

Intermolecular forces occur between particles. Intramolecular forces hold particles together.

What happens when a gas is less compressed?

Less density (more space to move)

Why does a pile of snow slowly shrink even on days when the temperature never rises above the freezing point of water?

Some of the snow sublimes.

how the addition or removal of energy can cause a phase change?

The addition of energy increases the kinetic energy of the particles, which reduces the intermolecular forces between the particles. As energy is removed, the kinetic energy of the particles decreases and intermolecular forces increase.

Why does solid iodine sublime readily? Use your knowledge of intermolecular forces to explain.

The dispersion forces that hold iodine molecules together in its solid crystal are relatively weak so when those bonds break, the atoms can move apart directly from the solid to the gas state.

A solid being heated stays at a constant temperature until it is completely melted. What happens to the heat energy put into the system during that time?

The energy is used to break the intermolecular forces holding the particles of the solid together.

List three PHASE changes that require energy and three that release energy.

requires energy—melting, sublimation, vaporization; releases energy—freezing, deposition, condensation

If I have more bonds, I have (stronger, weaker) IMF's

stronger

what determines a substance's state at a given temperature?

the IMF's