THERMODYNAMICS TEST

Heat

thermal equilibrium/ transfer of internal KE from greater concentration to lower concentration

what happens to the internal energy of a system when work is done on it? What happens to its temperature?

they both increase

1st Law of Thermodynamics

total increase in thermal energy of a system in the sum of the work done on it and the heat added to it

What does the 1st law of thermodynamics say and what is the math formula associated with it?

total increase in thermal energy of a system is the sum of the work done on it and the heat added to it. ***

Radiation

transfers heat through electromagnetic radiation; occurs even in an empty space (vacuum)/ transfers in all directions/ requires no contact/ go through transparent materials

Convection

transfers heat through moving currents in gases or liquids/ no currents= no convection (hot air rises, wind)

Conduction

transfers heat through objects touching/ atoms collide

Thermal contract

when a system exchanges energy through the process of heat.

Efficiency

%E= actual-theoretical/theoretical X100

Explain why substances will eventually always reach thermal equilibrium

**

List some examples of the 2nd law of thermo (entropy)

1) the spreading of smoke from a fire 2) ice cube in a glass of water

Phase Change

Transitions between solid, liquid, and gaseous phases

Adiabatic process

compressing or expanding a gas in a closed system so that no energy escapes

What are the 3 methods of heat transfer and what type of medium do they work in?

conduction--> solid convection--> liquid, gas radiation--> gas

High absorption

dark objects/ dull objects

Conductor

easily allow heat transfer (metals)

Heat of fusion

energy for the phase change between a liquid and a solid to occur without a change in temperature.

Law of Conservation of Energy

energy neither created or destroyed

What is the relationship between the temperature of a substance and heat?

heat=Q=mcp change in T--> directly related

Explain which way heat flows

hot--> cold, higher concentration to lower concentration

How does the 2nd law of thermodynamics relate to the direction of heat flow?

it requires heat to flow from hot to cold naturally

Low absorption

light objects/ shiny objects

Temperature

measure of average amount of KE of the molecules of a substance. (temp increases, average KE of molecules increases/ temp decreases, average KE of molecules decreases)

Why does a piece of room temperature metal feel cooler to the touch than a piece of wood or paper?

metal has a better ability to transfer heat from your own fingers.

2nd Law of Thermodynamics

natural processes go in a direction that increases the total entropy of the universe

There are many types of internal energy, but an increase in only one type will result in a temperature increase. Which type of internal energy is tied to temperature? How are they related?

Kinetic energy--> the faster the particles move, the more KE and temp. (directly related)

Entopy

Meauser of amount of disorder in a system (hot to cold)

Insulator

slow down heat transfer (materials with air pockets)

Thermodynamics

study of heat and its transformation into mechanical energy

Specific heat

the heat required to raise the temperature of the unit mass of a given substance by a given amount (usually one degree). (cp)

Explain why having a higher temperature does not necessarily mean having more KE overall.

the larger the container, the less KE you will have.

Heat of vaporization

the quantity of heat required at a specified temperature to convert unit mass of liquid into vapor.

Thermal Equilibrium

the same temperature

What is the meaning of thermodynamics?

the study of how heat changes

Thermal Expansion

the tendency of matter to change in volume in response to a change in temperature, through heat transfer.