When a sample of potassium nitrate is heated, oxygen gas is produced. This gas, collected in a 750 milliliter flask, has a pressure of 2.8 atmosphere and the temperature is recorded to be 53.6°C. How many moles of oxygen gas are produced in this reaction?
(R = 0.08205 L atm/K mol)
To find the number of moles of oxygen gas produced in this reaction, we can use the Ideal Gas Law equation:
PV = nRT
Where:
P = pressure in atm
V = volume in liters
n = number of moles
R = ideal gas constant (0.08205 L atm/K mol)
T = temperature in Kelvin
First, we need to convert the given volume from milliliters to liters:
750 milliliters = 750/1000 = 0.75 liters
Now, let's convert the temperature from Celsius to Kelvin:
T(K) = T(°C) + 273.15
= 53.6 + 273.15
= 326.75 K
Now, we can use the equation to find the number of moles (n):
n = PV / RT
Substituting the given values:
n = (2.8 atm) x (0.75 L) / (0.08205 L atm/K mol) x (326.75 K)
Simplifying:
n = 2.1 atm L / 26.86 L atm/K mol
n ≈ 0.0782 mol
Therefore, approximately 0.0782 moles of oxygen gas are produced in this reaction.
2KNO3 ==> 2KNO2 + O2
The equation above is not necessary for solution of the problem.
Use PV = nRT and solve for n.