1. Extended tier only

Fluorine, the most reactive halogen, forms compounds with the other halogens. It forms two compounds with bromine.

Deduce their formulae from the following information.

compound 1 The mass of one mole of this compound is 137 g. Its formula is .................................

[1]

compound 2 0.02 moles of this compound contain 0.02 moles of bromine atoms and 0.1 moles of fluorine atoms. Its formula is .................................

[1]