Here is a negative exponents learning exercise where there are a total of 47 problems. It is divided into three sections. Each section states a rule for working with negative exponents, gives an example of how to use the rule to solve the problem, and then there are quite a few practice problems.
Exponential BlissWell, maybe. Check out different resources all pertaining to exponent rules. The main focus is on integer exponents, but the last resources in the collection include rational exponents and a brief connection to radicals. No solving required, just simplifying expressions.7th - 10th Math