Answer:
1.88x10²³ molecules of N₂
Step-by-step explanation:
If the N₂ is at STP conditions and occupies 7L of volume, like the CH₄ we can apply the Ideal Gases Law to find out the moles.
STP = 273K (temperature) and 1atm (pressure)
P .V = n .R.T
1atm . 7L = n . 0.082L.atm/mol.K . 273K
(1atm . 7L) / (0.082L.atm/mol.K . 273K) = n
0.312 moles = n
These are the moles of N₂, so how many molecules are on it?
1 mol has NA molecules
0.312 moles have ____ ( 0.312 .NA) = 1.88x10²³
NA = Avogadro's number (6.02x10²³)