Answer
If the mass of a radioactive sample is doubled, the disintegration constant remains the same.
Work Step by Step
We can write an expression for the disintegration constant:
$\lambda = \frac{ln(2)}{T_{1/2}}$
$T_{1/2}$ is the half-life
Note that $T_{1/2}$ does not depend on the mass.
If the mass is doubled, the value of $T_{1/2}$ does not change.
It follows that the disintegration constant does not change.
Therefore, if the mass of a radioactive sample is doubled, the disintegration constant remains the same.
