.ANSWER
[tex]\text{CoBr}_2.7H_{2_{}}O[/tex]STEP-BY-STEP EXPLANATION
From the question given, you were asked to name a compound
Cobalt (II) Bromide Heptahydrate
The heptahydrate in the compound means it has 7 molecules of water
Therefore, the chemical formula can be written below as
[tex]\text{CoBr}_2.7H_2O[/tex]