Question

In this prelab exercise, you will calculate how to prepare solutions that you will make in lab. Below is an example of how to prepare a solution with a specific concentration: Prepare 600 mL of a 3 M NaOH solution. Begin by reviewing the molarity equation:

Answer 1

Explanation:

$Molarity=\frac{\text{Moles of compound}}{\text{Volume of solution (L)}}$

Moles of compound =

$\frac{\text{mass of compound}}{\text{Molar mass of compound}}$

We have ;

Volume of solution = 600 mL = 0.600 L ( 1 mL = 0.001 L)

Moles of NaOH = n

Molarity of the solution = 3 M

$3M=\frac{n}{0.600 L}$

n = 3 M × 0.600 L = 1.800 mol

Mass of 1.800 mole sof NaOH :

1.800 mol × 40 g/mol = 72.0 g

Preparation:

Weight 72.0 grams of sodium hydroxide and add it to the 500 mL of volumetric flask along with some water. Dissolve the all the solute by adding small proportion of water. After the solution becomes clear make the water upto the mark of 500 ml.

Transfer the solution to a bigger beaker  and 100 mL of water more to it.