How to determine NaCl in a sample

Procedure:

 
1. Weigh 3-5g sample in 400 ml beaker

2. Add 200 ml hot distilled water and stir to dissolve

3. Add 25 ml 30% Calcium Nitrate, stir well, filter and cool 

4. Transfer filtrate to 500 ml vol. flask and dilute to the mark.  

5. Take 100 ml aliquot from Step 4 to 250 ml erlenmeyer flask, add drops of 

   5% Potassium Chromate solution

6. Titrate using 0.1N Silver Nitrate from yellow to brick red 

Calculations: 

                     V X 292.5 

% NaCl  = --------------

                     W X 100