Chemical Kinetics  MCQs

MCQs of Chemical Kinetics

Showing 151 to 160 out of 228 Questions
151.
P and Q are different reactants t12 for p is 5 seconds and t12 for Q is 15 seconds. If initially [p] = 4 [Q ], after what time will the concentration of both reactants be equal ?
(a) 75 seconds
(b) 15 seconds
(c) 150 seconds
(d) 30 seconds
Answer:

Option (b)

152.
t12 is 10 minutes for reaction,

N2O5g  2NO2g + 12O2g

If initial quantity of N2O5 is 10.0 g. What will be its amount left after 40 minutes ?

(a) 0.625 g
(b) 2.50 g
(c) 1.0 g
(d) 0.25 g
Answer:

Option (a)

153.
t12 is 100 days for 10 g radioactive substance. Hence t12 for 20 g substance will be _____ .
(a) 100 days
(b) 200 days
(c) 10 days
(d) 5 days
Answer:

Option (a)

154.
t12 for C14 = 5730 years. If in green vegetation reactivity of C14 is 30 dpm and a wooden idol shows 5 dpm reactivity of C14, what is the age of the idol ?
(a) 12,520 years
(b) 11,460 years
(c) 17,190 years
(d) 22,920 years
Answer:

Option (b)

155.
For first order reaction K = 10-3 min-1 . Its t23 = _____ .
(a) 3300 min
(b) 2200 min
(c) 1500 min
(d) None of the above
Answer:

Option (d)

156.
To which order if reaction does the following equation belong K = 2.303t logaa - x ?
(a) Zero
(b) First
(c) x order
(d) Third
Answer:

Option (b)

157.
t12 for C14 is 5760 years. The time required to convert 200 g into 25 g is _____ .
(a) 17280 years
(b) 800 years
(c) 11520 years
(d) 720 years
Answer:

Option (a)

158.
If t12 for a radioactive element in N years, the time required for its complete decay is _____ .
(a) 12N years
(b) 12N2 years
(c) 2N years
(d) Infinite years
Answer:

Option (d)

159.
For a first order reaction, if 40 minutes are required to decrease the concentration of reactant from 6 moles to 3 moles, what time is required in such reaction to decrease 12 moles of reactant to 6 moles ?
(a) 20 minutes
(b) 40 minutes
(c) 80 minutes
(d) 160 minutes
Answer:

Option (b)

160.
For a first order reaction, initial concentration 0.8 M decreases to 0.1 M in 60 minutes. What is half life period t12 ?
(a) 20 minutes
(b) 30 minutes
(c) 40 minutes
(d) 15 minutes
Answer:

Option (a)

Showing 151 to 160 out of 228 Questions