Hi,

Preparation of 100 mL of 1 N NaOH solution :-

Dissolve 4.5 g of sodium hydroxide in 100 mL distilled water, allow to cool, and then add saturated barium hydroxide solution drop wise with stirring until a precipitate is formed. Leave aside allowing for complete precipitation, filter, and collect the filtrate to be standardized against 1 N HCl solution.

Procedure :-

• Wash the burette with the D. W. and the titrant (NaOH)
• Fill the burette with NaOH to a level (adjust it)
• Wash a 20 mL – bulb pipette with D. W. then by a little of HCl solution; fill it to the mark with the acid
• Transfer the acid into a clean conical fask; add D.W. (50 mL)
• Add 2 drops of phenolphthalein indicator
• Start titration by adding NaOH solution drop wise with continuous stirring until the solution changes from colourless to pink
• Record the volume of NaOH solution used and calculate the normality.

Hope this helps.

Good luck.