An unknown polyatomic ion (XY) combines with Br to form the following compound (XY)Br3. What is the charge on XY? A.+3
B.-3
C.+1
D.-1
I need help please

Bohr's model could only explain the spectra of which type of atoms? single atoms with one electron single atoms with more than one electron bonded atoms with one electron bonded atoms with more than one electron

Transportation is the largest single source of air pollution in the united states. air pollution can harm the environment and human health. which technology could offer a solution to this problem? mufflers that reduce noise motors that run on electricity tires that improve gas mileage

0.09 moles of sodium sulfate in 12 ml of solution