How many moles of oxygen must be placed
in a 3.00 L container to exert a pressure of 2.00 atm at 25.0°C?
Which variables are given?

0.24 moles of oxygen must be placed  in a 3.00 L container to exert a pressure of 2.00 atm at 25.0°C.

The variables given are Pressure, volume  and temperature.

Explanation:

Given:

P = 2 atm

V = 3 litres

T = 25 degrees or 298.15 K by using the formula 25 + 273.17 = K

R  = 0.082057 L atm/ mole K

n (number of moles) = ?

The equation used is of Ideal Gas law:

PV = nRT

n =

Putting the values given for oxygen gas in the Ideal gas equation, we get

n =

  = 0.24

Thus, from the calculation using Ideal Gas law it is found that 0.24 moles of oxygen must be placed in a container.

Ideal gas law equation is used as it tells the relation between temperature, pressure and volume of the gas.

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