Answer
Yes, the number is in scientific notation.
Work Step by Step
A number in scientific notation is written as the product of two factors in the form $a×10^n$, where $n$ is an integer and $1\leq |a| <10$.
The number $7.3\times10^{-5}$ meets both of these criteria, as $7.3$ is between $1$ and $10$, and $-5$ is an integer.
