Properties of Gases

Kinetic-molecular theory describes the behavior of gases in terms of particles in motion.

Kinetic-Molecular

Theory

Gases are made from small particles separated from one another by empty space.

Kinetic-Molecular

TheoryGas particles are in constant, random motion and collisions between particles are elastic.The mass and speed of

gas particles determine the kinetic energy of a gas sample.

Behavior of Gases

Gases have a very low density.

Gases can be compressed or expanded.

DiffusionThe movement of one material through another.

Gas escaping a container through a tiny opening.

Effusion

Gas Behavior RecapGases diffuse into spaces filled

with other gases.

At the same temperature, gases with smaller masses move faster than heavy gases.

Gases effuse through small openings at measureable rates.

Gas Properties Practice1) What does KMT assume about

the size and positioning of gas particles?A) particles are large and

move slowlyB) particles are small and

move quicklyC) particles are large and far

apartD) particles are small and far

apart

Gas Properties Practice2) True or False:

According to KMT, gas particles are in constant, random motion. The particles lose energy when they collide with other gas particles.

Gas Properties Practice3) Larger, slow-moving gases

could have the same kinetic energy as smaller, fast-moving gases. The relationship that explains this is:

A) mass/velocity = KEB) mass * velocity = KEC) ½ mass * velocity = KED) KE = m * c2

Gas Properties Practice4) Perfume sprayed into a room

quickly spreads out until it is evenly distributed in lower concentrations than the original spray. This is based on ________ cause by ___________.

A) effusion, kinetic energyB) diffusion, random particle

motionC) compression, variable

density

Gas Properties Practice5) Gases escaping a container

through a small opening are measured to determine their relative velocities. This process is an example of:

A) effusion of gasesB) diffusion of gasesC) kinetic energy of gasesD) compression of gases

Gas Properties Practice6) At the same temperature, H2

gas will move ______ Cl2 gas.

A) slower thanB) the same speedC) faster than