chapter 4- heat and the second law of thermodynamics

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Which has a greater amount of entropy?

Air at 0oC Air at 20oC Air at -20oC *Air at 40oC

The standard used to calibrate Celsius thermometers is:

absolute zero *pure water liquid CO2 (dry ice) pure ethanol pure mercury

what is an example of convection?

boiling water- hot water rises, cold water sinks, cycle repeats

Energy can be transferred through a vacuum by:

both conduction and convection conduction only both convection and radiation *radiation only convection only

what is the unit for heat?

calories

Heat will only flow spontaneously from:

cold to hot *hot to cold hot to hotter cold to cold

Sunlight hitting dark roof tiles would and heating up a house would be an example of __________ .

conduction *radiation insulation work convection

Entropy is the measure of a system's:

conduction convection temperature heat capacity *disorder

Radiation is heat transfer by:

convection kinetic energy of molecules *electromagnetic waves of radiation stopping atomic motion conduction

A system that moves toward a higher state of order also moves toward a lower state of:

convection power *entropy insulation efficiency

entropy measures

disorder

radiation

doesn't need a travel medium

A term that compares how vigorous atoms are moving in a substance is:

potential energy emulsion *temperature heat kinetics

Daniel Fahrenheit invented temperature scale for which 0 represented:

the coldest day in Amsterdam the temperature of dry ice (solid CO2) the melting point of ice the freezing point of water *the coldest temperature he could obtain for salt water

how do we determine the efficiency of an enzyme?

the second law of thermodynamics

equation to convert to Fahrenheit

(1.8 x _____ C) +32

equation to convert to celcius

(____ F - 32) / 1.8

Twenty calories of heat energy will raise the temperature of 5 grams of water

*4o C 5o C 20o C 100o C

A calorie is the amount of heat energy necessary to raise the temperature of one gram of water by one degree

*Celsius English Kelvin Fahrenheit

Which of the following is the definition of a calorie?

*The amount of heat required to raise the temperature of 1 g of water initially at room temperature by 1oC. The amount of heat required to raise the temperature of 10 g of water initially at room temperature by 100oC. The amount of heat required to boil 1 g of water that is initially at 99oC. The amount of heat required to melt 1 g of ice that is initially 30oF.

As energy is transferred from one trophic level to the next,

*some energy is always lost in the form of heat the amount of energy lost is replaced by the sun all the energy is converted to chemical energy energy is converted into mechanical energy

The measure of the ability of a material to absorb heat is referred to as its

*specific heat capacity specific radiation ability specific conduction ability specific convection ability

Which of these represents the coldest temperature?

0 degree Celsius Freezing point of CO2 (dry ice) 0 degrees Fahrenheit *0 degrees Kelvin -100 degrees Celsius

In the Kelvin scale, water boils at

212o 100o *373o 32o

If the temperature of an object changes by 5oC then it also changes by:

5 Newtons 5 degrees Fahrenheit *5 degrees K (kelvin) 278 degrees K

Specific Heat Capacity

A measure of the ability of a material to absorb heat energy,defined as the quantity of heat required to raise the temperature of a gram of thatmaterial by 1ºC. Water displays the largest heat capacity of any common substance

Temperature

A quantity that reflects how vigorously atoms are moving and colliding ina material

Convection Cell

A region in a fluid in which heat is continuously being transferred by abulk motion of heated fluid from a heat source to the surface of the fluid, where heat isreleased. he cooled fluid then sinks and the cycle repeats.

Absolute zero is defined as the temperature at which:

All of the liquid has frozen lowest temperature ever observed with normal devices the freezing point of water, molecule crystallize *molecular and atomic vibration is zero; all heat extracted

Second Law of Thermodynamic

Any one of three equivalentstatements: (1) heat will not low spontaneously from a colder to a hotter body; (2) it isimpossible to construct a machine that does nothing but convert heat into useful work;and (3) the entropy of an isolated system always increases

Equation for efficiency

Efficiency = useful energy output/total energy input

First law of thermodynamics

Energy cannot be created or destroyed

Which statement best represents the second law of thermodynamics?

Energy may change from one form to another over and over again. Heat will not flow spontaneously from a hot to a cold body. *Every isolated system becomes more disordered with time. Scientists have constructed an engine that does nothing but convert heat to useful work. The total amount of energy in the universe is constant.

Water freezes at 0o in the _______ temperature scale.

Fahrenheit Kelvin *Celsius English

what are the different temperature scales?

Fahrenheit, Celsius, Kelvin

Another way of stating the Second Law of Thermodynamics is which of the following?

In order to increase the entropy of a system, work must be done on it by an external agent. It is impossible to decrease the entropy of a system. *In order to decrease the entropy of a system, work much be done on it by an external agent. The entropy of any system remains constant or increases.

In science, heat is commonly measured in what unit?

Specific heat capacity Degrees *Calories Watts Newtons

Thermal Conductivity

The ability of a material to transfer heat energy from onemolecule to the next by conduction. When thermal conductivity is low, as in wood orfiberglass insulation, the transfer of heat is slowed down.

Efficiency

The amount of work you get from an engine, divided by the amount of energyyou put in; a quantification of the loss of useful energy

Conduction

The movement of heat by collisions between vibrat- ing atoms ormolecules; one of three mechanisms by which heat moves

Absolute Zero

The temperature, zero kelvins, at which no energy can be extracted fromatoms; the coldest attainable tempera- ture, which is equal to -273.16oC or -459.67o

Entropy

The thermodynamic quantity that describes the degree of randomness of asystem. he greater the disorder or randomness, the higher the statistical probability ofthe state, and the higher the entropy.

Radiation

The transfer of heat by electromagnetic radiation. he only one of the threemechanisms of heat transfer that does not require atoms or molecules to facilitate thetransfer process.

Convection

The transfer of heat by the physical motion of masses of fluid. Dense,cooler luids (liquids and gases) descend in bulk and displace rising warmer luids, whichare less dense. One of three mechanisms by which heat moves.

The transfer of heat in the form of electromagnetic waves is called

chemical energy *radiation conduction convection

what is insulation for animals?

feathers

Freezing ice from liquid water is an example of going to a lower state of:

force work *entropy power insulation

The heat island effect in cities creates convection cells:

from cool concrete, which conducts heat from the Earth which do not affect the weather in any way that can be measured which are usually too small to affect temperature *by drawing in cool moist air from the suburbs which results in less rain falling in cities than in the surrounding areas

Temperature is a measure of:

how much energy a substance contains *the average kinetic energy of the atoms within a substance the amount of heat in a substance the average potential energy of the atoms within a substance how fast heat is moving in a substance

You add heat to a solid and cause it to melt. The resulting configuration is:

less disordered and at lower entropy. *more disordered and at higher entropy. equally disordered and at lower entropy. equally disordered and at higher entropy.

every isolated system becomes

more disordered with time.

What is the only way heat can be transferred within a solid piece of metal?

radiation convection force work *conduction

The transfer of heat by density - driven motion of gases or fluids is referred to as

radiation thermal movement *convection conduction

Which substance has the lowest specific heat capacity?

rock or tile water steam ice *copper

what substance has the highest specific heat?

water

Through which material will heat be conducted the best?

wool fur fat water *steel

A car converts energy and therefore represents a system. If gasoline is the material input, was is the material output?

work of getting the driver somewhere heat on the road from the tires force of the car's inertia *CO2 emissions to the atmosphere heat in the engine cylinders


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