Assay of Boric Acid NF

Question 1

Dissolve about ____ of Boric acid, accurately weighed, in 100 mL of a mixture of equal volumes of glycerin and water, previously neutralized to phenolphthalein TS, and titrate with 1 N sodium hydroxide VS. Discharge the pink color by the addition of 50 mL of glycerin, neutralized to phenolphthalein TS, and continue the titration until the pink color reappears. Each mL of 1 N sodium hydroxide is equivalent to 61.83 mg of H3BO3

Answer 1

2 g

Question 2

Dissolve about 2g of Boric acid, accurately weighed, in 100 mL of a mixture of equal volumes of glycerin and water, previously neutralized to ___________, and titrate with 1 N sodium hydroxide VS. Discharge the pink color by the addition of 50 mL of glycerin, neutralized to phenolphthalein TS, and continue the titration until the pink color reappears. Each mL of 1 N sodium hydroxide is equivalent to 61.83 mg of H3BO3

Answer 2

phenolphthalein TS

Question 3

Dissolve about 2g of Boric acid, accurately weighed, in 100 mL of a mixture of equal volumes of glycerin and water, previously neutralized to phenolphthalein TS, and titrate with _______ VS. Discharge the pink color by the addition of 50 mL of glycerin, neutralized to phenolphthalein TS, and continue the titration until the pink color reappears. Each mL of 1 N sodium hydroxide is equivalent to 61.83 mg of H3BO3

Answer 3

1 N sodium hydroxide

Question 4

Dissolve about 2g of Boric acid, accurately weighed, in 100 mL of a mixture of equal volumes of glycerin and water, previously neutralized to phenolphthalein TS, and titrate with 1 N sodium hydroxide VS. Discharge the pink color by the addition of _____, neutralized to phenolphthalein TS, and continue the titration until the pink color reappears. Each mL of 1 N sodium hydroxide is equivalent to 61.83 mg of H3BO3

Answer 4

50 mL of glycerin

Question 5

Dissolve about 2g of Boric acid, accurately weighed, in 100 mL of a mixture of equal volumes of glycerin and water, previously neutralized to phenolphthalein TS, and titrate with 1 N sodium hydroxide VS. Discharge the pink color by the addition of 50 mL of glycerin, neutralized to phenolphthalein TS, and continue the titration until the pink color reappears. Each mL of 1 N sodium hydroxide is equivalent to ____ of H3BO3

Answer 5

61.83 mg