Heat Flashcards
Temperature
A measure of the kinetic energy of the constituent particles (kelvin)
Heat
Energy in transfer due to a temperature difference (J)
Second law of thermodynamics
The heat flow statement. Heat flows spontaneously from a substance at a higher temperature to a substance at a lower temperature and does not flow spontaneously in the reverse direction.
Third law of thermodynamics
It is not possible to lower the temperature of any system to absolute zero in a finite number of steps.
Thermometer
Instrument of measuring temperature
Thermometric property
A property that changes with temperature
Linear expantion
The fractional change per unit length per degree Celcius or kelvin temperature change.
Cubic expansitivity
The coefficient of cubic expansion for a solid is the fractional change per unit volume per degree celcius or K temperature change.
joulemetry
Heat is supplied or removed in the changing of the temperature of a substance. The heat that must be supplied or removed to change to change the temperature of a substance.
Heat (Q) can be negative and positive
+Q = heat is added to / gained by a substance
-Q = Heat is removed from / lost by a substance.
Calorimetry
If there is no heat loss to the surrounding, the heat lost by the hotter object equals the heat gained by the cooled ones.
Heat capacity
The heat capacity of a body is the amount of heat exchanged by the body for a temperature change of 1 C degrees.
Specific heat capacity
The specific heat capacity of a body is the amount of heat exchanged by 1Kg of the body for a temperature change of 1 c degrees.
The law of heat exchnage
The heat lost by a object is equal to the heat gained by the object to which the heat is transferred.
Phase change
Heat supplied or removed to change the phase of a substance.
Latent heat
The heat exchanged during a phase change without a temperature change
Specific latent heat
The heat exchanged during a phase change of 1Kg of a substance without a temperature change
Specific latent heat fusion
The amount of heat exchanged when 1 Kg of liquid changes to 1 Kg solid without a temperature change
Vaparation
The amount of heat exchanged when 1 Kg liquid changes to 1 Kg vapour without a temperature change.
Sublimition
The amount of heat required to change 1 Kg of solid to 1Kg of vapour without a temperature change
Ideal gas law
The absolute pressure P of an ideal gas is directly proportional to take the kelvin temperature T and the number of moles n of the gas and inversely proportional to the volume V of gas.
Boyles law
The volume of an enclosed mass of gas is inversely proportional to the pressure at constant temperature.
Charles law
The volume of an enclosed mass of gas is directly proportional to the absolute temperature at a constant pressure
Guy lussacs law
The pressure of an enclosed mass of gas is directly proportional to the absolute temperature if the volume is kept constant
