# How to Calculate Enthalpy of Vaporization? ##### Joseph Hebert
Owner at - HVAC Buster

Joseph is an HVAC technician and a hobbyist blogger. He’s been working as an HVAC technician for almost 13 years, and he started blogging just...Read more

In order to calculate the enthalpy of vaporization, you need to know the heat capacity of the liquid and its boiling point. The heat capacity is a measure of how much heat is required to raise the temperature of a substance by one degree Celsius. The boiling point is the temperature at which a substance changes from a liquid to a gas.

To calculate the enthalpy of vaporization, you will need to use the equation: q = m * Cp * (Tb – T) where q is the amount of heat required, m is the mass of the liquid, Cp is the heat capacity, Tb is boiling point, and T is temperature.

• Determine the boiling point of the liquid at atmospheric pressure
• This can be done by looking up the boiling point in a reference book, or by measuring the temperature at which the liquid boils in a lab setting
• Measure the heat capacity of the liquid
• This can be done experimentally, or by looking up the heat capacity in a reference book
• Calculate the enthalpy of vaporization using the equation: ∆Hvap=−Cp×(Tb−T) where Cp is the heat capacity of the liquid, Tb is boiling point, and T is temperature

## How Do You Calculate the Enthalpy of Vaporization Given the Boiling Point?

The enthalpy of vaporization, also known as the heat of vaporization or latent heat of vaporization, is the amount of energy required to convert a liquid into a gas. The boiling point is the temperature at which this process occurs. To calculate the enthalpy of vaporization, you need to know the boiling point and specific heat capacity of the liquid.

The formula for calculating the enthalpy of vaporization is: Hvap = (boiling point – temperature) x specific heat capacity where Hvap is the enthalpy of vaporization, boiling point is the temperature at which the liquid boils, and temperature is the current temperature.

For water, the boiling point is 100°C and the specific heat capacity is 4.184 J/g°C. This gives us an equation of: Hvap = (100 – t) x 4.184

where t is temperature in degrees Celsius. Therefore, to calculate the enthalpy of vaporization for water at 80°C, we would plug in our values to get:

## How Do You Calculate Enthalpy of Vaporization from Slope?

In order to calculate the enthalpy of vaporization from slope, you will need to know the heat of vaporization and the temperature at which it occurs. The heat of vaporization is the amount of heat required to convert a liquid into a gas. The temperature at which this occurs is known as the boiling point.

To calculate the enthalpy of vaporization, you will need to use the following equation: H = (heat of vaporization) * (temperature at which it occurs) For example, let’s say that we want to calculate the enthalpy of water.

The heat of vaporization for water is 2260 kJ/mol and its boiling point is 100°C. We would plug these values into our equation like so: H = (2260 kJ/mol) * (100°C)

## How Do You Find the Enthalpy of Vaporization With Temperature And Pressure?

In order to find the enthalpy of vaporization with temperature and pressure, you will need to use the Clausius-Clapeyron equation. This equation relates the change in entropy (S) to the change in enthalpy (H), temperature (T), and pressure (P). The general form of this equation is as follows:

ΔS = ΔH/T – ΔP/ρ where ρ is the molar density of the substance. For a pure liquid, the molar density is simply the mass density divided by the molar mass.

To solve for ΔH, we can rearrange this equation to get: ΔH = TΔS + ΔP/ρ Now that we have an expression for ΔH, we can plug in values for T, S, P, and ρ.

For water, the molar mass is 18 g/mol and the boiling point at 1 atmosphere pressure is 100°C. The specific heat of water vapor at constant pressure is 2.01 kJ/(kg·K) and its latent heat of vaporization is 2256 kJ/kg. With these values plugged in, we get:

Delta H vap(kJ / mol) 40 C 819 60 C 1048

80 C 1244

## How Do You Calculate the Enthalpy of Vaporization Given Vapor Pressure?

In order to calculate the enthalpy of vaporization given vapor pressure, you must first determine the molar heat of vaporization. This can be done by using the Clausius-Clapeyron equation: ln(P2/P1) = (ΔHvap/R)(1/T2 – 1/T1)

where P1 and P2 are the vapor pressures at temperatures T1 and T2, ΔHvap is the molar heat of vaporization, and R is the universal gas constant. Once you have determined the molar heat of vaporization, you can then calculate the enthalpy of vaporization at a given temperature T as follows: ΔHvap(T) = ΔHvap + RTln(P/Po)

where P is the Vapor Pressure at temperature T and Po is a reference Vapor Pressure.

## How to Calculate Enthalpy of Vaporization of Water

The enthalpy of vaporization (ΔHvap) of water is the heat required to turn liquid water into water vapor. The molar enthalpy of vaporization is usually expressed in kJ/mol or J/mol, and at standard conditions for temperature and pressure, the value is 2260 kJ/mol. To calculate the ΔHvap of water, we need to know two things: the heat capacity of liquid water (Cp) and the heat capacity of water vapor (Cv).

The heat capacity of liquid water is 4.184 J/(g·K), and the heat capacity of water vapor is 1.996 J/(g·K). Now that we have all the information we need, let’s put it all together and calculate ΔHvap. We’ll use the equation:

ΔHvap = Cp(liquid) * (T2 – T1) + Cv(gas) * (T2 – T1) where T1 is the boiling point of liquid water (100°C) and T2 is the temperature of steam (212°C). Plugging in our values, we get:

λDegrees HVaporization = ((4.184 Joules)/(gram * Degrees Kelvin))*((212 Degrees Kelvin)-(100 Degrees Kelvin))+ ((1.996 Joules)/(gram * Degrees Kelvin))*((212 Degrees Kelvin)-(100 Degrees Kelvin)))

## How to Calculate Enthalpy of Vaporization from Boiling Point

When calculating the enthalpy of vaporization from boiling point, it is necessary to first determine the heat of vaporization. The heat of vaporization is the amount of heat required to transform a liquid into a gas at a given temperature. For water, this value is 2,260 J/g.

To calculate the enthalpy of vaporization, we must multiply the heat of vaporization by the number of moles being transformed. The boiling point is the temperature at which a liquid turns into a gas. For water, this occurs at 100°C (212°F).

To calculate the enthalpy of vaporization from boiling point, we must subtract the boiling point from the starting temperature. For our example, we will subtract 20°C from 100°C to get 80°C. Now that we have all of our information, we can finally calculate the enthalpy of vaporization.

To do so, we simply multiply the heat of vaporization by the numberof molesbeing transformed and divide by 1000:

## How to Calculate Enthalpy of Vaporization from Slope

In order to calculate the enthalpy of vaporization from slope, you will need to use the Clausius-Clapeyron equation. This equation relates the change in entropy (S) to the change in enthalpy (H). The slope of this line is equal to the ratio of these two values: H/S.

To find the value of H, you must first find the value of S. This can be done by using a steam table or an online calculator. Once you have found the value of S, you can then plug it into the Clausius-Clapeyron equation to solve for H. The answer you get will be in units of kJ/mol.

## What is the Enthalpy of Vaporization of Water

The Enthalpy of Vaporization of Water is the heat required to change one mole of water from a liquid state at its boiling point to a gaseous state at its vapor pressure. The molar enthalpy of vaporization is usually given in units of kJ/mol. The Enthalpy of Vaporization of Water is important in many areas, including thermodynamics, vapor-liquid equilibrium, and non-equilibrium situations.

## Conclusion

In order to calculate the enthalpy of vaporization, you will need to know the heat of vaporization and the atmospheric pressure. The heat of vaporization is the energy required to convert a liquid into a gas. The atmospheric pressure is the force exerted by the atmosphere on a given area.

To calculate the enthalpy of vaporization, you will need to use the following equation: H = (heat of vaporization) * (atmospheric pressure) Where H is the enthalpy of vaporization, heat of vaporization is the energy required to convert a liquid into a gas, and atmospheric pressure is the force exerted by the atmosphere on a given area. Joseph is an HVAC technician and a hobbyist blogger. He’s been working as an HVAC technician for almost 13 years, and he started blogging just a couple of years ago. Joseph loves to talk about HVAC devices, their uses, maintenance, installation, fixing, and different problems people face with their HVAC devices. He created Hvacbuster to share his knowledge and decade of experiences with people who don’t have any prior knowledge about these devices.