The half-life period of a radioactive element X is same as the mean-li...
∴ λx = 0.693 λY
λx < λY. Now, rate of decay = λN
Initially, number of atoms (N) of both are equal but since λY < λx, therefore Y will decay at a faster rate than x.
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The half-life period of a radioactive element X is same as the mean-li...
The half-life period of a radioactive element is the time it takes for half of the radioactive atoms in a sample to decay. The mean-life time of a radioactive element is the average time it takes for an atom to decay. In this scenario, element X has a half-life period equal to the mean-life time of element Y.
a) X and Y have the same decay rate initially:
- This statement is not correct. The decay rate of a radioactive element is determined by the number of atoms decaying per unit time. The half-life period and mean-life time do not provide information about the initial decay rate.
b) X and Y decay at the same rate always:
- This statement is not correct either. The decay rate of a radioactive element depends on the number of remaining radioactive atoms. As time passes, the number of atoms of both elements X and Y will decrease, but they will not necessarily decay at the same rate.
c) Y will decay at a faster rate than X:
- This statement is correct. Since the mean-life time of element Y is equal to the half-life period of element X, it means that on average, element Y decays faster than element X. The mean-life time represents the average time it takes for an atom to decay, so it can be inferred that Y has a faster decay rate.
d) X will decay at a faster rate than Y:
- This statement is incorrect. As mentioned above, the mean-life time of element Y is equal to the half-life period of element X, indicating that Y decays faster than X. Therefore, X will not decay at a faster rate than Y.
In summary, the correct answer is option 'C' - Y will decay at a faster rate than X because the mean-life time of Y is equal to the half-life period of X.