Answer
Calcium Fluoride - CaF$_{2}$
Work Step by Step
1. To begin, write the formula of the first element with its charge. Ca$^{2+}$
2. Then write the formula of the second element (fluoride is fluorine) along with its charge. F$^{-}$
3. Cross down the charges of both of the elements (+2 and -1) to get:
$$CaF_{2}$$
