Question

Calculate the volume occupied by 4.045×10²³ molecules of oxygen at 27°C having a pressure of 0.935 bar ​

Answer 1

Number of molecules = 4.045 x 1023

p = 700 torr = 700/760 atm

T = 27 + 273 = 300 K

R = 0.082 litre atm K-1 mol-1

n = {No. of molecules}/{6.023 x 1023}

= {4.045 x 1023}/{6.023 x 1023} = 0.672 mol

Now, pV = nRT or V = nRT/P

or

, V = {(0.672 mol) x (0.082 litre atm.mol-1 K-1)(300 K)}/{(700/760 atm)}

= 17.95 litre