J.R. S. answered 09/02/19
Ph.D. in Biochemistry--University Professor--Chemistry Tutor
Balanced equation is Hg(l)+Br2(l)——->HgBr2(s)
moles Hg used = 10 g x 1 mole/200.6 g = 0.04985 moles
moles Br2 used = 9 g x 1 mol/159.8 g = 0.0563 mokes
Limiting reactant is Hg
moles HBr2 formed = 0.04985 mol Hg x 1 mol HgBr2/mol Hg = 0.04985 moles HBr2
mass HBr2 = 0.04985 mol x 360 g/mol = 17.946 g = 20 g (to 1 sig fig)