Spectrophotometric measurement of atmospheric carbon monoxide in Quiapo using the modified phosphomolybdic acid method

• Main Authors: Maglalang, Mary Grace B., Quibilan, Jose Mari C.
• Format: text
• Language: English
• Published: Animo Repository 1991
• Subjects: Carbon monoxide; Spectrophotometry; Chemistry
• Online Access: https://animorepository.dlsu.edu.ph/etd_bachelors/5731
• Institution: De La Salle University

The concentration of atmospheric carbon monoxide in Quiapo was measured by spectrophotometrically determining the concentration of the molybdenum blue complex formed by the reaction of carbon monoxide with phosphomolybdic acid. The wavelength for the analysis was determined to be 690 nanometers. At this wavelength, the absorbance of the molybdenum blue complex was at its maximum. To make the modified phosphomolybdic acid method more suitable for the measurement of low levels of carbon monoxide the palladium (II), which served as the catalyst for the reaction was reduced prior to the preparation of the phosphomolybdic acid reagant solution. The carbon monoxide concentration in the air samples ranged from 20 to 50 parts per million which exceeds the allowable limit set by the National Pollution Control Commission of 10 parts per million for an eight-hour continuous exposure.