The activity of an old piece of wood is just 25% of the fresh piece of wood. If t1/2 of C-14 is 6000 yr, the age of piece of wood is
6000 yr
3000 yr
9000 yr
12000 yr
For a first order reaction at 27C, the ratio of time required for 75% completion to 25% completion of reaction is
3.0
2.303
4.8
0.477
If a plot of log10 C versus t gives a straight line for a given reaction, then the reaction is
zero order
first order
second order
third order
B.
first order
A graph between the log concentration (log C) of reactent and time t for the first order, reaction gives a straight line, whose slope is equal to
Hence, the order of the above reaction is one.
The half-life period of a first order reaction is 1 min 40 s. Calculate its rate constant.
6.93
6.93
6.93
If 50% of a radioactive substance dissociates in 15 min, then the time taken by substance to dissociate 99% will be
50 min
100 min
99 min
150 min
A certain nuclide has a half-life period of 30 min. If a sample containing 600 atoms is allowed to decay for 90 min, how many atoms will remain ?
200 atoms
450 atoms
75 atoms
150 atoms
Which is a correct integrated rate equation?
- d (a - x) = kdt
All are integrated rate equations
For which order reaction, the unit of rate constant is time-1?
Zero order
First order
Second order
Third order