fill the blanks -6
The temperature does not change during a .....although the amount of energy added is large.
phase transition
The internal energy of a substance includes both potential energy of intermolecular forces and kinetic energy of.... motion.
random
The energy required to melt Ig of a solid at its melting temperature is referred to as ...... for that substance.
the latent heat of melting
If there is a well stirred mixture of ice and water at thermal equilibrium in a container, then the temperature of the mixture is......
0°
If a liquid is forced to evaporate, it will act as a .... agent
cooling
A refrigerator must extract heat from a..... region and release it into a region of ..... temperature.
cold ; higher
The energy required to melt a mass m of a substance can be calculated by.....
Q=m hf
We feel warmer on a humid day because the level of moisture in the air inhibits the evaporation of....
perspiration
Ice is much more effective as a cooling agent than cold water because of ..... required to melt the ice.
internal energy
The mass of water vapor per unit volume of saturated air is the....
saturation vapor density
..... of any liquid is the temperature at which the vapor pressure is equal to the atmospheric pressure.
boiling point
Steam has.... internal energy than water and water has.... internal energy content than ice.
higher ; higher
When ice melts into water, it absorbs thermal energy from its surroundings, but does not change.....
temperature
The most common units for the vapor density are.....
g/m^3 ; kg/m^3
Assume the air is progressively cooled while maintaining the moisture content constant. Then the relative humidity will... until it reaches....
rise ; 100%
Boiling point of any liquid is the.....at which the vapor pressure is equal to the atmospheric pressure.
temperature
The temperature at which the moisture content in the air saturates it is called the....
dew point
The transfer of internal energy mainly occurs by one of the following three mechanisms:...
1)conduction ; 2)convection ; 3) radiation
The efficacy of heat conduction depends on the.... of collisions and..... transferred during each collision.
number ; amount of energy
..... is the main mechanism for heat loss from buildings
in winter.
radiation
The quantity DT/ Dxis referred to as...
thermal gradient
Fourier's law tells us that doubling the thickness of a clothing will ...... the rate of heat loss from the body.
halve
Central heating systems, which heat and circulate a closed volume of air, will.....the relative humidity.
reduce
..... refers to heat transfer by the movement of fluids.
convection
Air is a poor conductor, but it can efficiently transfer heat by....
convection
The movements of fluids which transfer heat are called....
convection currents
The body obtains energy by the.... of foods.
oxidation
To take place, both .....and..... require material medium.
conduction ; convection
The temperature of 500 g of water is raised from 10 °C to 40 °C. The energy needed to do this is about ......cal and..... J
15000 ; 62700
The ratio of.... to......at a given temperature is referred to as relative humidity.
actual vapor density ; saturation vapor density