To find the pressure exerted by a mixture of gases in a container, we can use the ideal gas law, which is expressed as PV = nRT. In this equation, P represents pressure, V is volume, n is the number of moles of gas, R is the ideal gas constant, and T is the temperature in Kelvin. Let's break this down step by step.
Step 1: Convert Temperature to Kelvin
The temperature given is 27 degrees Celsius. To convert this to Kelvin, we add 273.15:
T(K) = 27 + 273.15 = 300.15 K
Step 2: Calculate Total Moles of Gas
Next, we need to find the total number of moles of gas in the mixture. We have:
- 0.5 moles of oxygen (O2)
- 0.5 moles of nitrogen (N2)
- 0.25 moles of carbon dioxide (CO2)
Adding these together gives:
Total moles (n) = 0.5 + 0.5 + 0.25 = 1.25 moles
Step 3: Use the Ideal Gas Law
Now we can substitute the values into the ideal gas law. The volume (V) of the container is given as 5 liters, and the ideal gas constant (R) is typically 0.0821 L·atm/(K·mol) when using liters and atmospheres.
Now, substituting the values into the equation:
P = nRT / V
P = (1.25 moles) * (0.0821 L·atm/(K·mol)) * (300.15 K) / (5 L)
Step 4: Calculate the Pressure
Now, let's perform the calculation:
P = (1.25 * 0.0821 * 300.15) / 5
P = (30.703125) / 5
P = 6.140625 atm
Final Result
Therefore, the pressure exerted by the mixture of gases in the container is approximately 6.14 atm.
This calculation illustrates how the ideal gas law can be applied to determine the pressure of a gas mixture under specific conditions. Understanding these principles is essential in fields like chemistry and engineering, where gas behavior is a fundamental concept.