Question

How many moles of oxygen gas, o2, are in a storage tank with a volume of 1.000×105 l at stp?

Answer 1

STP means standard temperature and pressure which is equivalent to 273 K and 1 atm, respectively. Assuming ideal gas behavior, the solution for this problem is as follows:

PV = nRT
Solve for n,
n = RT/PV
n = (0.0821 L-atm/mol-K)(273 K)/(1 atm)(1×10⁵ L)
n = 2.24×10⁻⁴ moles

Answer 2

Explanation:

Ideal gas law states that the product of pressure and volume is directly proportional to the absolute temperature and gas constant.

Mathematically,          PV = nRT

where,         P = pressure

                   V = volume

                   n = number of moles

                  R = gas constant

                  T = temperature

At STP (Standard temperature and pressure) the value of temperature is 273 K and pressure is 1 atm.

Therefore, calculate moles of oxygen as follows.

                         PV = nRT

or,              $n = \frac{PV}{RT}$

                            = $\frac{1 atm \times 1.0 \times 10^{5}L}{0.0821 L atm/K mol \times 273 K}$  

                            = $\frac{1.0 \times 10^{5} mol}{22.4133}$

                            = $4.5 \times 10^{3}$ mol

Thus, we can conclude that there are $4.5 \times 10^{3}$ moles of oxygen gas are in the storage tank.