Question

${ }_{92}^{238} U$ is known to undergo radioactive decay to form ${ }_{82}^{206} Pb$ by emitting alpha and beta particles. A rock initially contained $68 \times 10^{-6} g$ of ${ }_{92}{ }^{238} U$. If the number of alpha particles that itwould emit during its radioactive decay of ${ }_{92}^{238} U$ to ${ }_{82}{ }^{206} Pb$ in three half-lives is $Z \times 10^{18}$, then what is the value of $Z$ ?

Answer 1

The value of Z is 1.21