title: Spectrophotometric determination of formaldehyde in air.
abstract: A spectrophotometric method for the determination of formaldehyde in air is described, based on the colour reaction of formaldehyde, p-aminoazobenzene and sulphur dioxide in hydrochloric acid medium. Beer's law is obeyed at 505 nm in the range 2-12 mug of formaldehyde per 25ml of final solution (0.08-0.48 ppm). Optimum conditions for colour development, and possible interferences, have been studied.
authors.affiliation: Department of Chemistry, Ravishankar University, Raipur, 492 010, India.
authors.forename: P
authors.initials: P
authors.lastname: Verma
authors.forename: V K
authors.initials: VK
authors.lastname: Gupta