Class 11 Record Experiment 3

 EXPERIEMNT 3 - MAKING OF A STANDARD SOLUTION (Write , draw in LHS OF THE RECORD) 

a) Transfering sodium carbonate                                        b) diluting the solution

c) adding last few ml dropwise                                            d) standard solution 

EXPERIMENT :  3    (WRITE IN RHS)                                                                                        

PREPARATION OF 0.1M SODIUM CARBONATE SOLUTION

AIM :- 

To prepare 0.1M sodium carbonate solution 

THEORY :-

Sodium carbonate is a primary standard that is it is easily available in state of high purity and is highly soluble in water. Sodium carbonate Na2CO3 has molar mass of 106 g/mol. To prepare 0.1M sodium carbonate solution, 10.6g of Na2CO3 is dissolved in one litre of the solution. Therefore to prepare 0.1M sodium carbonate solution, 250ml = 10.6/4 = 2.650 g of sodium carbonate are dissolved in lesser quantity of water and the solution diluted to exactly 250ml. 

APPARATUS:-

Electronic balance, watch glass, glass rod, 250ml measuring flask, wash bottle, funnel.

PROCEDURE:-

1. Take a watch glass, wash it with distilled water and then dry it.

2. Switch on electronic balance, keep the dry watch glass, tare the weight to zero then slowly carefully accurately add 2.650g of sodium carbonate and record the weight in the observation note book.

3. Transfer gently and carefully 2.650g of sodium carbonate from the watch glass into a clean and dry 250ml measuring flask using a funnel. Wash the watch glass with distilled water with the help of a wash bottle to transfer the particles sticking to it into the funnel. Use approximately 50ml distilled water for this purpose.

4. Wash funnel several times with distilled water by using a wash bottle to transfer the sticking particles into the measuring flask. While washing the funnel, add water in small amounts. The volume of the distilled water used for this purpose should not be more than 50ml.

5. Finally wash the funnel thoroughly with distilled water with the help of a wash bottle to transfer the solution sticking to the funnel into the measuring flask. 

6. Swirl the measuring flask till solid sodium carbonate dissolves.

7. Add enough distilled water to the measuring flask carefully upto just below the etched mark on it. With the help of the wash bottle. 

8. Add the last few ml of distilled water dropwise until the lower level of the meniscus just touches the mark on the measuring flask

9. Stopper the measuring flask and shake gently to make the solution uniform throughout. LABEL IT AS 0.1M SODIUM CARBONATE SOLUTION.

RESULT :-  250ml 0.1M  sodium carbonate solution is prepared