How many molecules of O2 are present in a 3.90L flask at a temperature of 273K and a pressure of 1.00 atm

Given:

Volume of O2, V = 3.90 L

Temperature of O2, T = 273 K

Pressure P = 1.00 atm

To determine:

Molecules of O2

Explanation:

From Ideal gas law-

PV = nRT

where n = number of moles of O2

R = gas constant = 0.0821 L atm/mol-K

n = PV/RT = 1*3.90/0.0821*273 = 0.1740 moles of O2

1 mole of O2 contains 6.023 * 10²³ molecules

0.1740 moles of O2 corresponds to:

=6.023 * 10²³ molecules*0.1740 moles of O2/1 mole of O2

= 1.048 * 10²³ molecules of O2