We can rearrange the ideal gas equation:
PV = nRT, where n is the number of moles equivalent to:
n = mass / Mr
PV = mRT/Mr
m/V = PMr/RT
density = PMr / RT; where Mr and R are constant.
Use pv=nrT
where p is the pressure,
v is the volume,
n is the number of mole (which can be equal to mass /mr),
T is the temperature in kelvin,
and r is (molar constant) = 8.31 (units)
SI unites are based on multiplying or dividing by 10, 100, 1,000, 10,000 (and so on...) depending on the unit you're solving for.
The answer to this is B, solids with a repeating atomic pattern.
