Get Advice on Live Video Call
Earn $ Cash $ with
consultations on Bissoy App

Thermal death of microorganisms in the liquid medium follows first order kinetics. If the initial cell concentration in the fermentation medium is 10<sup>8</sup> cells mL<sup>-1</sup> and the final acceptable contamination level is 10<sup>-3</sup> cells, for how long should 1 m<sup>3</sup> medium be treated at temperature of 120°C (thermal deactivation rate constant = 0.23 min<sup>-1</sup>) to achieve acceptable load?

Correct Answer: 110 min

If 'Δx' represents adherent oxide layer thickness and 't' is time, which of the following curves represents diffusion controlled oxidation kinetics?
Metallurgical Thermodynamics and Kinetics mcq question image

If k is the rate constant for a reaction and T is the absolute temperature in the given figure, the activation energy for the reaction is . . . . . . . . J/K mole.
Metallurgical Thermodynamics and Kinetics mcq question image

S1: Different countries show different pattern of growth.
P: Many others have a high birth rate with a low death rate.
Q: Some have a high birth rate and still have a high death rate.
R: The developing countries show the most rapid growth rate.
S: Some others like the European nations, have a low birth rate and a low death rate.
S6: Compared to this in Europe the growth rate is low.

The Proper sequence should be:

A pollutant P degrades according to first order kinetics. An aqueous stream containing P at 2 kmole/m3 and volumetric flow rate 1 m3/h requires a mixed flow reactor of volume V to bring down the pollutant level to 0.5 kmole/m3. The inlet concentration of the pollutant is now doubled and the volumetric flow rate is tripled. If the pollutant level is to be brought down to the same level of 0.5 kmole/m3, the volume of the mixed flow reactor should be increased by a factor of

In batch reaction time with enzyme deactivation, calculate the first-order deactivation rate constant. (Given – so = 12 mM; vmax = 9 mM h-1; Km = 8.9 mM; sf = 1.2 mM; th = 4.4 h).

For the reaction, A = X + Y, the respective concentrations are CA, CX and CY. The forward reaction rate constant is kf and the backward reaction rate constant is kb. Choose the correct statement from the following:
P. At equilibrium, kf CA > kB CxCy
Q. If the reaction is irreversible than, kb CXCY = 0
R. The backward reaction rate will essentially be first order, if the forward reaction rate is first order.
S. Activation energy for the first order forward reaction will be independent of temperature.

Batch fermentation of glucose to ethanol yields a productivity of 4.5 g-1L h-1. If the yeast cell concentration in the fermentation broth is 5% (v/v) and the intracellular NAD+/NADH concentration in the yeast cells is 10 μM, the cycling rate of NAD+ ⇌ NADH will be

Select the correct plot of Gibbs free energy (G) Vs. Temperature (T) for a single component system from the following:
Metallurgical Thermodynamics and Kinetics mcq question image

Which of the following statement(s) is/are CORRECT for antigen activated effector T cells?
P. CD4+ cells make contact with macrophages and stimulate their microbicidal activity.
Q. CD4+ cells make contact with B cells and stimulate them to differentiate into plasma cells.
R. CD8+ cells make contact with B cells and stimulate them to differentiate into plasma cells.
S. CD8+ cells make contact with virus infected cells and kill them.

The kinetics of the disintegration of baker's yeast cells in a bead mill is described as $$\frac{{dp}}{{dt}} = K\left( {{P_m} - P} \right)$$   , where P is the concentration of protein released, m is the maximum protein concentration achievable, K is the first order rate constant and is 0.5 h−1 for the system studied. The time required for the release of 90% of the intracellular proteins will be: