Question

51) Which of the following represents the equation for a first-order half-life? A) + 1/2 - kAl. B) + 12 = 0.623 9)1/2 = 2[4] D)t1/2 = 21 E) 1/2 = [A]o 52) Which of the following represents the equation for a second-order half-life? A) t1/2 = WAL B)t1/2 = 0.693 C) 1/2 - 2K 0.693 D) t1/2 = Tai E)t1/2 = [A]o 53) Which of the following represents the equation for a zero-order half-life? A) + 1/2 - BA1 B)t1/2 = 0,023 C)1/2 FAK D)+1/2 - Flo E) t1/2 T. 54) The rate constant for a second-order reaction is 0.54 M-Is-1. What is the half-life of this reaction if the initial concentration is 0.33 M?

Answer 1

Answer (51)

for first order reaction half life is given by

     t1/2 = 0.693/k here k = rate constant and t1/2 = half life

option B is answer

Answer(52)

for second order reaction

half life t1/2 = 1/k[A0] here k = rate constant and [A0] = initial concentration

option A is answer

Answer (53)

for zero order reaction t1/2= [A0]/2k

option C is answer

Answer (54)

for second order reaction

half life t1/2 = 1/k[A0] here k = rate constant= 0.54 M^-1s^-1 and [A0] = initial concentration =0.33

t1/2= 1/0.54*0.33 = 5.6 seconds