Standard temperature is 273 K
Standard pressure is 1 atm
We use the ideal gas equation to find out density of nitrogen gas in g/L
Ideal gas equation:
![PV = nRT\\ PV = (\frac{Mass}{Molar mass)}RT\\ P(Molar mass) = (\frac{Mass}{Volume})RT\\ \frac{Mass}{Volume}=\frac{P(molar mass)}{RT} \\ Density = \frac{P(Molar mass)}{RT}](https://tex.z-dn.net/?f=%20PV%20%3D%20nRT%5C%5C%20%20PV%20%3D%20%28%5Cfrac%7BMass%7D%7BMolar%20mass%29%7DRT%5C%5C%20%20%20P%28Molar%20mass%29%20%3D%20%28%5Cfrac%7BMass%7D%7BVolume%7D%29RT%5C%5C%20%20%5Cfrac%7BMass%7D%7BVolume%7D%3D%5Cfrac%7BP%28molar%20mass%29%7D%7BRT%7D%20%5C%5C%20%20Density%20%3D%20%5Cfrac%7BP%28Molar%20mass%29%7D%7BRT%7D%20%20)
Molar mass of ![N_{2} = 28 g/mol](https://tex.z-dn.net/?f=%20N_%7B2%7D%20%3D%2028%20g%2Fmol%20%20)
Pressure = 1 atm
Temperature = 273 K
![Density = \frac{(1atm)(28 g/mol)}{(0.08206 \frac{L.atm}{mol.K})(273 K)}](https://tex.z-dn.net/?f=%20Density%20%3D%20%5Cfrac%7B%281atm%29%2828%20g%2Fmol%29%7D%7B%280.08206%20%5Cfrac%7BL.atm%7D%7Bmol.K%7D%29%28273%20K%29%7D%20%20%20)
= 1.25 g/L
Therefore, density of nitrogen gas at STP is 1.25 g/L
B - Sediment . Many layers of sediment slowly built up into a rock which turn into a fossil .