Preparation of 5M Sodium Chloride (NaCl)

Overview:

• NaCl is highly soluble in water. Its aqueous solution is clear and colorless.
• A 5M NaCl solution is easy to prepare.
• One liter of 5M NaCl solution can be prepared by dissolving 292 grams of NaCl powder in water.
• 5M NaCl solution is stable at room temperature and can be sterilized by autoclaving.

Requirements:

Reagents
♦ Sodium chloride (NaCl)
♦ Deionized / Milli-Q water

Equipment and disposables
♦ Measuring cylinder/volumetric flask
♦ Conical flask / Beaker
♦ Magnetic stirrer

Composition: 5 M Sodium chloride (NaCl)

Objective: Preparation of 1000 ml of 5 M Sodium chloride solution in water from NaCl powder.

Preparation

Step 1: Weigh out 292.2 g of Sodium chloride in an appropriate size beaker or conical flask ( 2 L volume). Add 800 ml deionized water.

Precaution:
Do not add 1000 ml of deionized/Milli-Q water. In most cases, solution volume increases when a large amount of solute is dissolved in a solvent.

Step 2: Dissolve NaCl using a magnetic stirrer or manual shaking with a glass stirring rod.

Tip:
You can heat the solution to 60°C to accelerate the dissolution process.

Step 3: Transfer solution to measuring cylinder or a volumetric flask and adjust the volume 1000 ml with deionized water. Mix it again.

Step 4:  Transfer the solution to an autoclavable bottle and sterilize it by autoclaving (20 minutes at 15 lb/sq.in. (psi) from 121-124°C on liquid cycle)

Storage:
Store the solution at room temperature.

Tip:
NaCl may precipitate with time. Dissolve it by shaking the bottle vigorously. 

Precautions: 
Don’t store the solution at 4°C.