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4. The elimination of carbon dioxide from pyruvate ions by a decarboxylase enzyme was monitored by measuring the partial pressure of the gas as it was formed. In one experiment, the partial pressure increased from zero to 100Pa in 422s in a first-order reaction. What is the rate constant of the reaction? CH3COCO2(aq)+H+(aq)CO2(g)+CH3CHO(aq) Data: Vol CO2 produced =250cm3,Vol solution =100cm3,T=293K, initial concentration of pyruvate ion [CH3COCO2]=3.23mmol/dm3,PCO2=100Pa at 422s, and PCO2=0 at 0 s. ans: 7.5105/s