Please help ASAP. C3H8 + 5O2 ---> 4H2O + 3CO2 1. How many moles of oxygen gas are needed to react with excess propane (C3H8) in order to form 5.32 moles of water?
2. What mass of carbon dioxide is produced from 13 grams of oxygen gas and excess propane?
3. What mass of propane is needed in order to produce 2.70 moles of water?

The two naturally occurring isotopes of chlorine are 35cl (34.969 amu, 75.77%) and 37cl (36.966 amu, 24.23%). the two naturally occurring isotopes of bromine are 79br (78.918 rm amu, 50.69%) and 81br (80.916 amu, 49.31%). chlorine and bromine combine to form bromine monochloride, brcl. 1. how many peaks will be present in a mass spectrum for brcl? the four combinations of molecule possible given these four isotopes are: 81br37cl, 81br35cl, 79br37cl, and 79br35cl. 2. what are the masses of the four different brcl molecules? express the masses using six significant figures, in decreasing numeric order (highest to lowest), separated by commas.