Ethanol is produced by anaerobic fermentation of glucose by Saccharomyces cerevisiae. For the particular strain of S. cerevisiae employed, the maintenance coefficient is 0.18 kg kg^{- 1} h^{- 1}, Yxs is 0.11 kg kg^-1, Y_PX is 3.9 kg kg^-1 and µ_max is 0.4 h^-1.  It is decided to investigate the possibility of using Zymomonas mobilis bacteria instead of yeast for making ethanol. Z. mobilis is known to produce ethanol under anaerobic conditions using a different metabolic pathway to that employed by yeast. Typical values of Yxs are lower than for yeast at about 0.06 kg kg^-1; on the other hand, the maintenance coefficient is higher at 2.2 kg kg ^-1 h ^-1. Ypx for Z. mobilis is 7.7 kg kg^-l; µ_max is 0.3 h- 1.  From stoichiometry, what is the maximum theoretical yield of ethanol from glucose                 

TLS Online TPP Program

#Question id: 21731

#Section 5: Bioprocess Engineering and Process Biotechnology

The smog constituent peroxyacetyl nitrate (PAN) dissociates into peroxyacetyl radicals and NO2(g) in a first order reaction with a half-life of 32 min. 

If the initial concentration of PAN in an air sample is 2.7×10¹⁵ molecules/L, what will be the concentration 2.24 h later?

TLS Online TPP Program

#Question id: 21732

#Section 5: Bioprocess Engineering and Process Biotechnology

Rate constants for the first-order decomposition of acetonedicarboxylic acid

CO(CH2COOH)2(aq) → CO(CH3)2(aq) + 2 CO2(g)

are k = 4.75 ×10^–4 s^–1 at 293 K and k = 1.63 ×10^–3 at 303 K. What is the activation energy, Ea, for this reaction?

TLS Online TPP Program

#Question id: 21733

#Section 5: Bioprocess Engineering and Process Biotechnology

A rate law __________.

TLS Online TPP Program

#Question id: 21734

#Section 5: Bioprocess Engineering and Process Biotechnology

Consider the following balanced equation.

Al₂O₃+6NaOH+12HF=2Na₃AlF₆+9H2O

The rate law for this reaction is rate=k[Al₂O₃]²[NaOH].

What is the rate constant for this reaction if the reaction proceeds at an initial rate of 0.005Ms when all of the reactants have initial concentrations of 0.02M?

TLS Online TPP Program

#Question id: 21735

#Section 5: Bioprocess Engineering and Process Biotechnology

Given the following equation (2A+B  3C). Which of the following correctly displays the rate of the reaction?

I. -Δ[A]/2Δt

II. Δ[B]/Δt

III. Δ[C]/3Δt

TLS Online TPP Program

#Question id: 21736

#Section 5: Bioprocess Engineering and Process Biotechnology

Which of the following is a classic example of a first-order reaction?