1. If 5 moles of dinitrogen (N^2) at STP, What would be the volume?
She's getting 4.48
Definitely not. Hard to say what went wrong not seeing the work.
2. What would be the density of any gas at STP thats got a molar mass of 64g/mole??
I tried doing this one, and got .35g/L
I am afraid that's wrong as well. Exact result depends a bit on what one means by STP (it is a bit ambiguous, not your fault), but should be much higher. Again, hard to help without seeing the work.