Thermodynamics

Momentum

Used to analyze collisions and explosions

Impluse

Change in momentum

In elastic collisions, kinetic energy is a) conserved or b) not conserved.

A) Conserved

In elastic collisions, momentum is a) not conserved or b) conserved.

B) Conserved

What do objects do in elastic collisions? (microscopic)

Bounce off each other

In inelastic collisions, kinetic energy is a) conserved or b) not conserved.

B) Not conserved

In inelastic collisions, momentum is a) conserved or b) not conserved.

A) Conserved

What do objects do in inelastic collisions? (microscopic)

Bounce off of each other

What do objects do in inelastic collisions? (macroscopic)

Stick together

Pressure (Pa)

The amount of force per area

Kinetic Energy (J)

Energy of motion

Heat

The transfer of thermal energy into a system

Cooling

The transfer of thermal energy out of a system

After many collisions of molecules from different systems, it will reach __________ _____________.

Thermal Equilibrium

Boyle’s Gas Law

Describes the relationship between pressure and volume

Charles’ Law

Describes the relationship between temperature and volume

Pressure Law

Describes the relationship between pressure and temperature

Are gas particles a) spaced out , b) close together, or c) somewhere in the middle?

A) Spaced out

Gas particles move _______ in a container.

Randomly

Are collisions between gas particles inelastic or elastic?

Elastic

As the temperature of gas particles increases, the average speed of the particles __________.

Increase

Maxwell Speed Distribution

Describes the distribution of speeds among particles in a gas

Mass (kg)

Amount of matter

Volume (m³)

Space occupied

Density (kg/m³)

Amount of matter per space

Solids

• Constant shape

• Constant mass

• Constant volume (cannot be compressed)

Liquids

• Takes shape of container

• Constant mass

• Constant volume (cannot be compressed)

Gas

• Constant mass

• Can be compressed

Ideal Gas Laws (List Four)

• Gas particles move in random straight lines

• Collisions between particles are elastic

• The temperature is proportional to the kinetic energy

• No intermolecular attraction between particles

At absolute zero, pressure is _______.

Zero

At absolute zero, ________ and _______ are at an all time low.

Entropy; Enthalpy

Conduction

Faster moving particles collide with slower moving particles and speed them up, increasing their temperature

Buoyancy

Force that pushes up on an object in water or air

Archimedes’ Principle

Buoyant force is equal in magnitude to the weight of the fluid displaced

Convection

Hot air rises

As a temperature of a fluid increases, its density _________.

Decreases

As the density of a fluid decreases, it experiences a larger ________ ________ and _____.

Buoyant force; rises

Radiation

Energy that moves from one place to another in a form that can be described as waves or particles

Internal Energy

Total energy of the systems

Isobaric

Pressure is constant

Isothermal

Temperature is constant; internal energy (U) = 0

Isovolumetric (Isochoric)

Volume is constant; Work = 0

Adiabatic

No heat is exchanged

What sign is work when gas is expanding? (Work done on the gas)

Negative

What sign is work when gas is being compressed? (Work done on the gas)

Positive

When a closed system is moving clockwise, work is ____________.

Negative

When a closed system is moving counterclockwise, work is ____________.

Positive

In a close system, the internal energy (U) is A) Equal to the amount of work done on the gas, B) Equal to the amount of temperature, or C) Zero.

C) Zero

How do you figure the net work based off of a graph? (closed system)

It is the area inside the closed shape.

Specific Heat

Amount of heat energy required to raise the temperature of one kilogram of a substance by one degree Celsius (or one Kelvin)

The rate at which energy transfers by conduction depends on…(Three Things)

• The material

• The physical dimensions

• Temperature difference

Zeroth Law of Thermodynamics

If system A and B are in thermodynamic equilibrium with system C, then systems A and B are in thermal equilibrium with each other

Entropy

Measure of the disorder or randomness in a system

When does maximum entropy occur?

When a system is in thermodynamic equilibrium

Second Law of Thermodynamic

Any energy transfer or transformation, the total entropy of a closed system will either increase or remain the same; it cannot decrease

When is the work being done on the gas?

When the volume is decreasing or being compressed

When is work being done by the gas?

When the volume is increasing or being expanded