Question

QUESTION 1

1.       One of the major concerns in fermented foodstuff is the presence of urethane in their products, as this compound is known to be carcinogenic. Therefore, the removal of urea, a precursor of urethane, must be achieved efficiently to comply with governmental limiting levels of urethane. One of the most common processes for the removal of urea in the industrial production of alcoholic beverages is the use of urease enzyme.  

          Using 10 g∙dm^-3 of urease, initial laboratory tests have determined the effect of urea concentration on the rate of the degradation reaction at 30 °C, and the following data was obtained:

   Urea substrate concentration, [S] (kmol m-3)	0.100	0.200	0.500	1.000
   Initial reaction rate, r (kmol m-3 s-1)	8.333	9.090	9.615	9.803

      Calculate the kinetic parameters of this enzyme reaction (Vm and Km) in the initial laboratory tests.

   MCQ Options:

   		Vm = 10 kmol m3 Km = 0.02 kmol m-3 s-1
   		Vm = 1 kmol m3 Km = 0.2 kmol m-3 s-1
   		Vm = 10 mol m3 h-1 Km = 0.02 mol m-3
   		Vm = 10 kmol m3 s-1 Km = 0.02 kmol m-3
   		Vm = 0.1 kmol m3 s-1 Km = 0.002 kmol m-3
   		Vm = 0.1 mol m3 h-1 Km = 0.04 mol m-3

2. Calculate the time needed to degrade 99% of the urea in a 0.5 dm³ solution in a batch reactor, at 30 °C, in the presence of urease. The initial concentration of urea in the reactor is 0.1 mol∙dm^-3 and the urease concentration is 2∙10^-4g∙dm^-3.

MCQ Options:

		29.62 mins
		29.62 seconds
		4.83 x 10-4 mins
		4.83 mins
		15.92 mins
		48.35 mins

Answer 1