# OVERVIEW

A 1N solution of Sodium hydroxide (NaOH) solution can easily be prepared by diluting if you have already concentrated 10N Sodium hydroxide solution. To prepare 100 ml of 1N solution, take 10 ml of 10 N stock solution in a measuring cylinder and adjust the volume to 100 ml by adding 90 ml of deionized or distilled water. The resulting solution of sodium hydroxide will be 1N. The detailed procedure is described below.

# REQUIREMENTS

Reagents and solutions
10N Sodium hydroxide (NaOH) solution
Deionized / Double distilled water

Equipment and disposables
Beaker
Magnetic stirrer (optional)

COMPOSITION
10 M NaOH solution

OBJECTIVE
Preparation of 100 ml of 1 N NaOH solution by diluting 10N NaOH solution

# PROCEDURE:

Use personal protective equipment (lab coat, gloves, goggles etc) for your safety and follow the guidelines of your institute.

## PART I: Calculate how much 10N Sodium Hydroxide Solution is required to prepare 100 ml of 1N NaOH solution

Step 1: Take 10 ml of 10N NaOH solution in a measuring cylinder. Add 90 ml of deionized/distilled water to make up the volume to 100 ml.

Step 1: Calculate how much concentrated stock solution is required to prepare 100 mL of 1M Sodium Hydroxide solution using the dilution method.
Dilution method is described in the post “Preparing Working Solution from Stock Solution by Dilution

Use the following formula to calculate the volume of 10N NaOH solution required for the preparation of 1 liter of 1N Sodium Hydroxide solution.

Formula:   Cf x Vf = CS x VS

Cf (concentration of diluted (final) solution) = 1 N
Vf (volume of diluted (final) solution) = 100 ml
CS (concentration of stock solution) = 10 N
VS (volume of stock solution) = ? (unknown)

Place all values in the formula:

1 x 100 = 10 x VS

VS = 1 x 100/ 10 = 10 ml

So you need 10 ml of 10 N concentrated Sodium Hydroxide solution to prepare 100 ml of 1N Sodium Hydroxide solution.

Step 3 (optional): Calculate the volume of solvent to be taken.

Final volume of diluted solution = 100 ml
Volume of concentrated solution = 10 ml
Volume of solvent (water) required = 100 – 10 = 90 ml

So you need to mix 10 ml of concentrated solution with 90 water to prepare 100 ml of 1N Sodium Hydroxide solution.

## PART II: Solution preparation

Step 4: Take 10 ml of 10N NaOH solution in a measuring cylinder. Add 90 ml of deionized/distilled water to make up the volume to 100 ml. Mix it.
Tips: You can cover the mouth of the measuring cylinder tightly with parafilm and mix the solution by inverting the cylinder a few times. Alternatively, you can also use a magnetic stirrer.

STORAGE
Solution can be stored at room temperature. 