Formaldehyde Solution

Formaldehyde Solution Formaldehyde; CH₂O  =  30.03 (50-00-0)

Analytical reagent grade of commerce containing not less than 34.0% w/v and not more than 37.0% w/v of CH₂O.

A colourless, aqueous solution with a lachrymatory vapour; weight per  ml, about 1.08  g.

Assay Dilute 5  ml to 1000  ml with water. To 10  ml of the solution add 25  ml of 0.05m iodine VS and 10  ml of 1m sodium hydroxide. Allow to stand for 5 minutes, add 11  ml of 1m hydrochloric acid and titrate the excess iodine with 0.1m sodium thiosulphate VS using 1  ml of starch solution added towards the end of the titration as indicator. Each  ml of 0.05m iodine VS is equivalent to 1.50  mg of CH₂O.

Store at a temperature between 15° and 25°.