#1) The Lewis structure of PF3 shows that central phosphorus atom has ___ nonbonding and ___ bonding electron pairs. #2) How many equivalent resonance forms can be drawn for CO3^-2? (carbon is the central atom) #3) The bond angle in NF3 is slightly less than ___? #4) Sample of gas (1.3mol) occupies ____L at 22 Celcius and 2.5 atm. #5)The formula weight of silver chromate (Ag2CrO4) is ______ amu #6) The molar volume of gas at STP is _____ L.