Answer
0, no reciprocal
Work Step by Step
We are given that a number $a=0$.
We know that the opposite of a number $a$ is $-a$, so the opposite of $a=0$ will be $-a=0$. In other words, the opposite of 0 is 0.
We know that the reciprocal of a nonzero number $a$ is the number $\frac{1}{a}$, where $a\times\frac{1}{a}=1$
However, 0 has no reciprocal, because there is no number that, when multiplied by 0, results in a product of 1.