The enzyme examase catalyses the following reaction, A - B where A is the reactant and B is the product A595 measurements were used to determine the catalytic activity of examase by measuring the rate at which B is produced. From this, the activity of the enzyme was determined to be 42 µmol/mL per minute. A standard albumin solution (concentration = 10 mg/mL) was used to prepare a standard curve of Abs595 vs amount of protein in mg. The protein assay was also performed using 100 ul of a 1 in 10 dilution of the original examase sample. For the absorbance measurements, it was determined that the sample used in the A595 measurement contains 1.2 mg of examase. Which of the following statements correctly gives the specific activity of examase? 1.0.35 U/mg O 2.0.035 U/mg O 3. 5040 U/mg O 4.35 U/mg O 5.3.5 U/mg

what is the activation energy? rate = r = k [I-]^1 [S2O82-]^1 Mixtures:             Temperatures (celsius):        Initial Rates: 1                                      21.9                               6.45 * 10-4 2                                     38.9                              3.54 * 10-4 3                                      2.4                               4.35 * 10-4

28. For the aqueous reaction I2 + HPO(OH)2 + H₂O → PO(OH)3 + 2 I¯ + 2 H* the following mechanism is proposed: HPO(OH)₂ P(OH)3 P(OH)3 + 12 → IP(OH)3* + I¯ IP(OH)3 + H₂O → PO(OH)3 + I + 2 H+ fast, unfavorable slow, irreversible fast Which observation is consistent with this mechanism? (A) The reaction is first order in both HPO(OH)2 and I₂. (B) The reaction rate is independent of the I₂ concentration. (C) The reaction goes faster as the concentration of H* is increased. (D) The reaction goes slower as the concentration of I- is increased.

A certain enzymatic reaction is found to be zero order with respect to the substrate being converted. The rate constant for the reaction is found to be 750 M s-1. The initial concentration of the substrate is 0.370 M. When the reaction is 50% complete, what is the rate of the reaction at that point? Give your answer in M s-1 but do not include units in your answer.

In aqueous solution buffered at a pH of 6.75 Penicillin G (molecular weight of 334.39 g/mole) undergoes hydrolysis via a pseudo first order reaction that has an activation energy of 77.3 kJ/mole and a pseudo first order rate constant of 1.58 x 10-7 s-1 at 30°C. What is the half life (in days) of Penicillin G under the conditions described?

Consider the following proposed reaction mechanism: (1) CIO (aq) + H,O(1)= HCIO(aq) + OH (aq) [fast] (2)I (aq) + HCIO(aq) → HIO(aq) + Cl¯(aq) [slow] (3) OH (aq) + HIO(aq) → H,O() + 10 (aq) [fast] Ignoring water, how many reaction intermediates are present? O 3 O 1 O 2

10. Which of the following statements is correct in enzyme kinetics, if S represents the substrate? At very low substrate concentration, the rate of enzyme reaction is zero order with respect to [S]. At very high substrate concentration, the rate of enzyme reaction is zero order with respect to [S]. At all substrate concentrations, the rate of enzyme reaction is zero order with respect to [S]. At all substrate concentrations, the rate of enzyme reaction is first order with respect to [S]. At very high substrate concentration, the rate of enzyme reaction is first order with respect to [S].

Temperature effect on the degradation of a multisulfa preparation was evaluated at 60 and 70°C. If the first-order reaction rate constants responsible for the degradation at these two temperatures were 8.2 x 10-4 and 1.96 x 10-3 hr-1, respectively, answer the following TWO questions.   Calculate the frequency factor, A, for the degradation of this drug within this temperature range (in hr-1).

For a drug to be effective in treating an illnens, its levels in the bloodstream must be maintained for a period of time. One way to measure the level of a drug in the body is to measure its rate of appearance in the urine. The rate of excretion of penicillin is first order, with a half-life of about 30. min. If a person receives an injecction of 21 mg of penicillin at t- 0, how much penicillin remains in the body after 3.0 hours? mg

5. What is the value for the rate constant, k? k = k'/1* = k = k"/0.5* = kavg r = k[OH°]*[ C25H3„N,'J" [OH] C2H,„N;'] r = 303