What is the boiling point of tap water with three tablespoons of table salt added?

Adding table salt to water raises its boiling point. The increase in boiling point is dependent on the concentration of dissolved solute particles (ions) in the solution.

The exact increase in boiling point can be calculated using the formula:

ΔTb = i * Kf * m

Where:

ΔTb = Change in boiling point

i = Van't Hoff factor (number of particles into which the solute dissociates)

Kf = ebullioscopic constant (a constant for the solvent)

m = molality of the solution (moles of solute per kilogram of solvent)

For a salt like sodium chloride (NaCl):

• i = 2 (since NaCl dissociates into 2 ions: Na⁺ and Cl⁻)
• Kf for water is approximately 0.512 °C kg/mol
• Three tablespoons of table salt is roughly 66 grams

It's important to note that the exact increase in boiling point would depend on the amount of water used in the mixture. However, for a rough estimate:

Let's assume the average tap water volume is around 1 liter (1000 grams).

The molality of the solution:

m = moles of salt / mass of water in kg

m = 0.066 kg / 1 kg = 0.066 mol/kg

Now, using the formula and assuming the given average values:

ΔTb = 2 * 0.512 °C kg/mol * 0.066 mol/kg ≈ 0.067 °C

Therefore, the boiling point of tap water with three tablespoons of table salt added would be raised by approximately 0.067 degrees Celsius above the normal boiling point of pure water, which is around 100 degrees Celsius at standard atmospheric pressure.