At this pressure, how many molecules of air would there be in a 50? c experimental chamber with a volume of 0.050 m3?

The pressure is p = 4.0 * 10 ^ - 11 Pa.

Then, use the ideal gas equation: pV = nRT

Call #m the number of molecules. #m is n * Avogadro's number, #m = nA = > n = #m/A

=> pV = (#m / A) RT = > #m = pV*A / (RT)

p = 4.0 * 10 ^ - 11Pa

V = 0.050m^3

A = 6.02 * 10^ 23

R = 8.314 J / (K*mol)

T = 50 + 273.15 K = 323.15 K

Now, plug in the numbers:

#m = 4.0 * 10^ - 11Pa * 0.050 m^3 * 6.02 * 10^ 23 (molec/mol) / (8.314 J / (K*mol) * 323.15K)

#m = 448,138,552 molecules