To prevent the presence of air, noble gases are placed over highly reactive chemicals to act as inert "blanketing" gases. A chemical engineer places a mixture of noble gases consisting of 4.50 g of He, 15.0 g of Ne, and 33.6 g of Kr in a piston-cylinder assembly at STP. Calculate the partial pressure of each gas.
PHe = __atm
PNe = __atm
PKr = __atm
There are a couple of ways to do this but the easiest probably is to use PV = nRT for each gas.
n for He = 4.50 g/4.003, plug in STP conditions and solve for P.
Same process for each of the others.
none of yall be helpin out
To calculate the partial pressure of each gas, we first need to understand the concepts of molar mass, mole, and ideal gas equation.
Step 1: Calculate the number of moles for each gas.
To find the number of moles, we divide the given mass of each gas by its molar mass. The molar mass of He is 4.003 g/mol, Ne is 20.18 g/mol, and Kr is 83.8 g/mol.
Number of moles of Helium (nHe) = 4.50 g / 4.003 g/mol
Number of moles of Neon (nNe) = 15.0 g / 20.18 g/mol
Number of moles of Krypton (nKr) = 33.6 g / 83.8 g/mol
Step 2: Calculate the total number of moles.
To find the total number of moles in the mixture, we add the moles of each gas.
Total moles (nTotal) = nHe + nNe + nKr
Step 3: Calculate the partial pressure of each gas using the ideal gas equation.
The ideal gas equation is given by:
PV = nRT
Since the temperature (T) and volume (V) are constant at STP (standard temperature and pressure), we can simplify the equation to:
P = (n/V) * R * T
Where P is the pressure, n is the number of moles, V is the volume, R is the ideal gas constant, and T is the temperature.
At STP, the volume is 1 mole of an ideal gas is 22.4 L, and the ideal gas constant (R) is 0.0821 L * atm / (mol * K).
Step 4: Substitute the values into the equation to find the partial pressure of each gas.
PHe = (nHe / nTotal) * R * T
PNe = (nNe / nTotal) * R * T
PKr = (nKr / nTotal) * R * T
Substitute the values and calculate the partial pressure of each gas.