# Heat Of Vaporization Formula

Heat of Vaporization Formula

What is Heat of Vaporization ?

The Heat of Vaporization is the quantity of heat that needs to be absorbed to vaporize a particular quantity of liquid at a constant temperature. If the solutions of vapor and liquid states are compared, the kinetic energy of the steam is proved to be higher than the kinetic energy of the fluid.

In other words, the heat of vaporization is the amount of heat required to turn particular quantity of liquid into vapor without any rise in the temperature of the fluid.

Heat of Vaporization Formula
Based on entropy and enthalpy of vaporization and relationship among them, the Heat of vaporization formula can be written as

Hv = q / m
Wherein,

Hv = heat of vaporization
q =heat
m = mass

Example1
If the heat of vaporization for water is 2257 j/g, calculate the amount of heat energy that must be applied to vaporize 145 grams of water.
Solution:
The heat of vaporization equation can be rearranged to solve for q, i.e.,

$H_{v}=\frac{q}{m}$

q = Hv x m

= 2257 x 145

Therefore q = 327265 J

Example 2
Determine the mass of water which can be vaporized at 100°C if 15500 J of heat energy is applied.

Solution:
Given:
Heat q = 15500

The heat of vaporization for water can be implemented, and the equation is rearranged to solve for mass.

$m=\frac{q}{H_{v}}$

= 15500 / 2257

= 6.867 g

#### Practise This Question

What is the fraction used to represent the orange colour parts?
Assume: In the given figures, triangle and squares have equal area.