# Which one is more concentrated 1 molar NaOH or 1 molal NaOH aqueous solution? Explain?

##### 1 Answer

Both solutions are dilute enough that they have the same concentrations within the uncertainty of measurement.

#### Explanation:

Let's calculate the percent by mass of each solution.

**1 mol/kg #"NaOH(aq)"#**

A 1 mol/kg

**1 mol/L #"NaOH(aq)"#**

A 1 mol/L

The density of the solution is 1.04 g/mL.

Hence,

Thus, both solutions have effectively the same concentration.