The energy required to completely separate the molecules, moving from liquid to gas, is much greater that if you were just to reduce their separation, solid to liquid. Hence the reason why the latent heat of vaporization is
greater that the latent heat of fusion
. … So it really isn’t a change in kinetic energy.
Why does water have a high latent heat of vaporisation?
Water forms fairly strong bonds with itself, for a liquid, and so has a
very exothermic (negative) heat of condensation
. In reverse this gives it a very high heat of vaporisation: a lot of energy is required to turn it into a gas.
Why is the heat of vaporization so high?
The heat of vaporization describes how much energy is needed to separate these bonds. Water has a high heat of vaporization
because hydrogen bonds form readily between the oxygen of one molecule and the hydrogens of other molecules
. These bonds hold the molecules together.
What does high latent heat of vaporization mean?
Likewise, the high latent heat of vaporization (see below), indicates that
when water vapor (derived from evaporation of water at the ocean’s surface driven by solar energy receipt at low latitudes) condenses into liquid droplets at high elevations or high latitude, the latent heat is released into the environment
.
Why is water’s high latent heat of vaporization biologically significant Give two reasons?
Water has high heat of vaporization:
This is due to
the hydrogen bonding
. As a result water has an unusually high boiling point for such a small molecule. The energy transferred to water molecules to allow then to vaporize results in loss of energy from their surroundings, thus cooling takes places.
Does water have a high latent heat of vaporization?
That is,
water has a high heat of vaporization
, the amount of energy needed to change one gram of a liquid substance to a gas at constant temperature. … In humans and other organisms, the evaporation of sweat, which is about 99% water, cools the body to maintain a steady temperature.
Does latent heat of vaporization change with pressure?
In conclusion if pressure increases, volume change decreases. So therefore
Latent heat of vaporization remains constant
.
What is sensible heat water?
Sensible heat of water: It is defined as
the quantity of heat absorbed by 1 kg ofwater when it is heated from 0°C (freezing point) to boiling point
.It is also called total heat (orenthalpy) of water or liquid heat invariably. It is reckoned from 0°C where sensible heat is takenas zero.
What is heating curve of water?
The heating curve for water shows
how the temperature of a given quantity of water changes as heat is added at a constant rate
. During a phase change, the temperature of the water remains constant, resulting in a plateau on the graph.
What is latent heat of vaporization of water?
Hint: Latent heat of vaporization is defined as the heat required to change 1 mole of liquid substance into gaseous form under standard atmospheric pressure. The value of heat of vaporization of water is equal to
40.8KJ/mol
.
What substance has the highest latent heat?
The magnitude of the latent heat is a measure of how strongly bound the molecules are to one another in the liquid and solid states. Note in the table above that
water
has the highest latent heat of vaporization. The next highest is ammonia, NH
3
, which is similar in many ways to water, H
2
O.
How can you detect latent heat?
Measuring latent heat
Latent heat can be
measured from a heating or cooling curve line graph
. If a heater of known power is used, such as a 60 W immersion heater that provides 60 J/s, the temperature of a known mass of ice can be monitored each second. This will generate a graph that looks like this.
What is the latent heat of steam?
As the latent heat of steam at atmospheric pressure is
2257 kJ/kg
the amount of flash steam produced will be 299/2257 = 0.133 kg/kg of condensate.
Is water a good solvent?
Water is capable of dissolving a variety of different substances, which is why it is such
a good solvent
. And, water is called the “universal solvent” because it dissolves more substances than any other liquid. … It is water’s chemical composition and physical attributes that make it such an excellent solvent.
What is the latent heat of vaporization of water in J kg?
The latent heat of vaporization of water is approximately
2,260kJ/kg
. 1 calorie = 4.186 J. Latent heat of vaporization of water = 539 cal/g = 2256 kJ/kg.
What makes water biologically useful?
Water’s extensive capability to dissolve a variety of molecules has earned it the designation of “
universal solvent
,” and it is this ability that makes water such an invaluable life-sustaining force. On a biological level, water’s role as a solvent helps cells transport and use substances like oxygen or nutrients.
