The chemical formula RbBr represents rubidium bromide, which is composed of two elements: rubidium (Rb) and bromine (Br). Among the options you provided:
- Cl (Chlorine)
- Br (Bromine)
- Rb (Rubidium)
- Ag (Silver)
The model that represents the substance with the chemical formula RbBr is Rb for rubidium and Br for bromine. However, if you're looking for the single element from the options given that is part of RbBr, the correct answer would be Br (bromine).