Answer:in a mass spectrum of BrCl four (4) peaks will be present
Step-by-step explanation:
Cl and Br both have two naturally occuring isotopes.Br has 79Br which has abundance50.69% and 81Br which has abundance 49.31%.Similarly two isotopes of Cl are 35Cl having abundance 75.77% and 37Cl having abundance 24.23%.Chlorine and bromine combine and form bromine monochloride .Now they can combine with each other in four possible combinations wich are 1(81Br37Cl) 2(81Br35Cl) 3(79Br37Cl) 4(79Br35Cl) .So these four combined isotopes will show four peaks in mass spectrum.