Question

Boiling point of pure tap water with two tablespoons of salt?

Answer 1

The boiling point elevation of a solvent by adding a non-volatile solute is called a colligative property where the nature (identity) of the solute is unimportant and only the amount of it counts. You wanna use this formula:

\(\Delta T= i*m*K_b\)

but you need some more information, how much water are you using?

Answer 2

I'm using one cup of water.

Answer 3

Correction, two cups**

Answer 4

so two cups of water and two tablespoons of salt?

Answer 5

Yep!

Answer 6

okay, we need to convert these to metric units of mass,

1 tablespoon = 14.786764843 g

1 cup = 0.236588 L = 236.6 mL (density of water is about 1 g/mL)

so 1 cup = 236.6 g

Answer 7

Ah, I see. It's starting to make sense!

Answer 8

okay, we need exactly how much mass there is of each.

Then find the moles of salt, \(moles=\dfrac{mass}{Molar~mass}\)

the find the molality: \(molality=\dfrac{moles~of~salt}{kg~of~water}\)

then finally: \(100^o+\Delta T=i*molality*K_b\)