NatSci2 - Heat and Temperature

8/8/2019 NatSci2 - Heat and Temperature

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NASC 2

USC-TC


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- the transition of matter from one state

to another.


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- the transition of matter from liquid to gaseous state.


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it happens when heat is added into the

substance

it occurs in the surface of the liquid

molecules that leave off the surface are energy

gainers

molecules that remain on the liquid are energy

losers

evaporation is a cooling process

perspiration is a form of evaporation.


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- the transition of matter from gaseous state

to liquid state.


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it occurs when heat is released by thegaseous substance

it is a warming process for thesurroundings

it provides explanation for the warmersurrounding temperature when it is about torain


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Air Well - is a structure or device that collects water by

promoting the condensation of moisture from air.


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A fog fence orfog collectoris an apparatus for collecting

liquid water from fog, using of a fine mesh or array of

parallel wires.


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Boiling, a type of phase transition , is the rapid

vaporizations of a liquid, which typically occurs whena liquid is heated to its boiling point, the temperature

at which the vapor pressure of the liquid is equal to

the pressure exerted on the liquid by the surrounding

environmental pressure.


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it happens when heat is added into the liquidsubstance

it occurs when the vapor pressure equals thesurrounding pressure which often times theatmospheric pressure at boiling temperatureof the given liquid

liquids can be boiled by increasing thetemperature in order to increase the vaporpressure or by decreasing the surroundingpressure

water can boil as low as 20 C or below.

boiling occurs at a constant temperaturecalled the boiling point of the given liquid

boiling is a cooling process in the part of theboiling liquid otherwise the temperature willcontinue to increase


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Water purification is the process of removing

undesirable chemicals, materials, and biological

contaminants from raw water.


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Melting (sometimes called fusion) is a physical

process that results in the phase change of a

substance from a solid to a liquid.


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application of heat or pressure causes the solid

substance to melt

it occurs at constant temperature called the melting point

the heat energy received by the substance is being used

to break the bonds of the solid


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- freezing or solidification is the process in which a liquid

turns into a solid when cold enough.


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Freezing primarily happens when heat is

further removed from the liquid substance that

diminishes molecular motion until finally the

molecules, on average, are moving so slowlythat the attractive motion between them are

able to cause cohesion

it occurs at a constant temperature called the

freezing point of the given substance

in most cases the freezing point is equal to the

melting point


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Heat Transfer is the transition of thermal energy from ahotter object to a cooler object ("object" in this sense

designating a complex collection of particles which is

capable of storing energy in many different ways).


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- the transfer of heat energy by collisionsbetween the particles in a substance (especially

as solid).


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it is the transfer of heat by direct contact of matter

transfer of heat by conduction is relayed by collisions of

particles (free electrons)

metals are good conductors since they contains one oremore loosely held electrons. Silver is the best, copper next,

aluminum and then iron.

wood, wool, straw, paper, cork and styrofoam are poor

conductors of heat since their outer electrons are firmlyattached to the molecules


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-the transfer of heat energy in a gas or liquid by meansof currents in the heated liquid. The fluid moves carrying

energy with it.


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it involves direct transfer of mass by convection or current

warmer fluid moves away from the heat source and cooler

fluid move toward the heat source to be warmed and then

move away, repeating the cycle as long as the difference in

temperature is maintained


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Electric Heaters serve as the source of heat,

producing convection in a room.


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In a convection oven, heat is made to circulate to

balance the distribution of hot air. A fan helps

circulate the hot air.


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- the transfer of energy by means of electromagnetic

waves


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it does not require any material medium to transfer heat

from one region to another

the energy so transmitted is called radiant energy,becoming heat only when it is absorbed

the Sun transfers it energy to theEarth through

radiation


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Allof science is nothing but a refinement of every day

thinking.

- AlbertEinstein

NatSci2 - Heat and Temperature

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