# Question b5d2b

Feb 15, 2016

One mole of sodium chloride is equivalent to two osmoles.

#### Explanation:

For starters, you need to make sure that you have clear understanding of what an osmole actually is.

As you know, a solution is made by dissolving a solute into a solvent. The molarity of the solution tells you how many moles of solute you get per liter of solution.

Now, osmoles are actually linked with a solution's osmotic pressure, which is proportional to the total concentration of solute particles present in solution.

This tells you that osmotic pressure, which is a colligative property, depends on how many particles of solute you have in solution.

An osmole thus represents a mole of particles produced in solution by one mole of solute.

As you know, sodium chloride is soluble in aqueous solution. When you dissolve one mole of sodium chloride in water, you produce one mole of sodium cations, ${\text{Na}}^{+}$, and one mole of chloride anions, ${\text{Cl}}^{-}$.

This means that every mole of sodium chloride produces two moles of ions in solution. Well, if an osmole represents a mole of particles produced in solution by a mole of solute, you can say that

1 color(red)(cancel(color(black)("mole NaCl"))) * "2 moles of ions"/(1color(red)(cancel(color(black)("mole NaCl")))) = "2 osmoles"

Similarly, four moles of sodium chloride will produce eight moles of ions in solutions

4color(red)(cancel(color(black)("moles NaCl"))) * "2 moles of ions"/(1color(red)(cancel(color(black)("mole NaCl")))) = "8 osmoles"#