posted by Anonymous .
Calculate the number of molecules of NBr3 in 25.0 g NBr3. Use a molar mass with at least as many significant figures as the data given.
How many moles do you have in 25.0 g NBr3? That is 25.0/molar mass = ?
How many molecules in that number of moles? Remember there are 6.02E23 molecules in a mole of anything Then multiply that by 3 since there are 3 atoms Br in each molecule of NBr3.