Created By : Rina Nayak

Reviewed By : Phani Ponnapalli

Last Updated : May 16, 2023


The Boiling Point Elevation Calculator will help you to determine the boiling point elevation of a solution. The solution boiling point elevation depends on the ebullioscopic constant, molarity. Give these two details as inputs and tap on the calculate button to get the result in a matter of seconds.

Molal Boiling Point Elevation Constant [Kb]
Molality [m]
Boiling Point Elevation [ΔTb]

What is Boiling Point Elevation?

Boiling point elevation is a colligative property of matter which depends on the solute-solvent ratio of the solution, not on the solute identity. It refers to the increase in the boiling point of the solvent when the solute is added to it. So, if the concentration of the solute in the solution is high, then the boiling point elevation becomes high.

Boiling Point Elevation Formula

The boiling point elevation is directly proportional to the solute concentration in the solution. The elevation in the boiling point formula is as follows:

The boiling point elevation is directly proportional to the solute concentration in the solution. The elevation in boiling point formula is as follows:

ΔT = i*K*m

Boiling Point of the Solution ΔT = Tsolution - Tsolvent 

Where,

i is the Van't Hoff factor

K is the ebullioscopic constant

m is the molarity of the solute

The ebullioscopic constant for different generally used solvents is given below.

Solvent K value (in oC.kg.mol-1)
Water 0.512
Phenol 3.04
Acetic Acid 3.07
Benzene 2.53
Chloroform 3.63

The Van't Hoff factor values for common solutions are along the lines:

Solution Van 't Hoff factor
Sugar in water 1
Calcium chloride(CaCl2) in water 2.9 or 3
Sodium chloride (NaCl) in water 1.9 or 2

How to Find the Boiling Point Elevation?

The simple steps to calculate the boiling point elevation of the solution are listed here:

  • Get the boiling point of the purse solvent from the question.
  • Find the molarity of the solute, ebullioscopic constant or boiling point elevation constant.
  • Multiply molarity, ebullioscopic constant, Van't Hoff factor.
  • The obtained product is boiling point elevation.

Example:

10 grams of a non-volatile and non-dissociating solute is dissolved in 200 grams of benzene. The resulting solution boils at a temperature of 81.2oC. Find the molar mass of the solute.

Solution:

Let x = the number of moles of solute.

The boiling point of pure benzene is 80.1oC and it’s ebullioscopic constant is 2.53oC/molal. From the boiling point elevation formula, the following relationship can be obtained:

(81.2oC – 80.1oC) = (1)*(2.53oC.kg.mol-1)(x/0.2 kg)

x = (1.1oC*0.2kg)/(2.53oC.kg.mol-1)

x = 0.0869 moles

Since 0.0869 moles of the solute has a mass of 10 grams, 1 mole of the solute will have a mass of 10/0.0869 grams, which is equal to 115.07 grams.

Therefore, the molar mass of the solute is 115.07 grams per mole.

FAQs on Boiling Point Elevation Calculator

1. Why molarity is used in boiling point elevation?

The molarity value of the solution is used in calculating boiling point elevation as its value does not change with the temperature change. A solution concentration is expressed in molarity and it is related to temperature changes, and vapour pressure.


2. What factors affect boiling point elevation?

The factors that affect boiling point elevation depend on the temperature, atmospheric temperature, ebullioscopic constant of the solvent, the molarity of the solution, and Van't Hoff factor.


3. How does boiling point elevation calculated?

The boiling point elevation of the solution can be calculated with the equation ΔT = i * Kb * m. Substitute the values in the formula and perform a multiplication operation to get the answer in a matter of seconds.


4. Does the boiling point elevation constant change?

Boiling point elevation is a constant that is equal to the change in the boiling point of one molar solution of the nonvolatile molecular solute.

1. At STP, how do you calculate the density of a gas?

A gas's density at STP. At STP, the formula D= M/V is used, where M is the molar mass and V is the molar volume of a gas (22.4 liter/mole).


2. Is the density of gases the same at STP?

All ideal gases have the same number density, they all have the same molar volume. This will be 22.4 liters at STP. This is useful for visualizing the distance between molecules in various samples. For example, A sample of liquid water has a mass density of 1 g mL-1.


3. At STP, which has a higher density: hydrogen or helium?

Hydrogen has a mass of 1.001 g/mole, while Helium has a mass of 4.002 g/mole. As a result, dividing the mass of one mole of an element by the volume of one mole of the gas at STP yields the density of each gas. Helium has a density of more than four times that of hydrogen.


4. What is the ammonia gas density at STP?

The ammonia gas density at STP is 0.761g/L.


5. What is the STP volume?

Standard temperature and pressure (STP) is a good set of conditions to use when comparing other gas properties. Gases have a volume of 22.4 L per mole at STP. The ideal gas law can be used to calculate gas densities.