A mixture of nitrogen and krypton gases, in a 6.51 L flask at 84 °C, contains 3.04 grams of nitrogen and 13.5 grams of krypton. The partial pressure of krypton in the flask is
atm and the total pressure in the flask is
atm.
mols = grams/atomic mass
mols Kr = 13.5/atomic mass Kr = ?
mols N2 = 3.04/molar mass N2 = ?
P = nRT
for partial pressure Kr plug in mols Kr for n and the T listed. R is 008206. Solve for P.
Do the same for partial pressure N2 but use mols N2 for n.
For total P just add them; i.e., Ptotal = PN2 + PKr
Post your work if you get stuck.
Sorry but I made a typo on R by leaving out a decimal. R is 0.08206
To find the partial pressure of krypton in the flask, we first need to calculate the moles of nitrogen and krypton present in the mixture.
The moles of nitrogen can be calculated using the formula:
moles = mass / molar mass
The molar mass of nitrogen (N₂) is approximately 28.0134 g/mol. Therefore, the moles of nitrogen in the mixture can be calculated as:
moles of nitrogen = 3.04 g / 28.0134 g/mol
Similarly, the moles of krypton can be calculated using the formula:
moles of krypton = 13.5 g / molar mass of krypton
The molar mass of krypton (Kr) is approximately 83.798 g/mol, so:
moles of krypton = 13.5 g / 83.798 g/mol
Now, we can calculate the partial pressure of krypton using Dalton's Law of Partial Pressures. According to Dalton's Law, the total pressure of the mixture is the sum of the individual partial pressures:
total pressure = partial pressure of nitrogen + partial pressure of krypton
Since we are given the total pressure and the moles of nitrogen, we can rearrange the equation to solve for the partial pressure of krypton:
partial pressure of krypton = total pressure - partial pressure of nitrogen
We can use the ideal gas law equation to calculate the partial pressure of nitrogen:
partial pressure of nitrogen = (moles of nitrogen * gas constant * temperature) / volume
The gas constant (R) is 0.0821 L·atm/(mol·K).
Finally, we substitute the given values into the equation to calculate the partial pressure of krypton.