Question

5.8 moles of neon is added to a 22.4l glass bottle containing 12.0g of helium. the temperature of the bottle and its contents are kept constant by submerging the bottle in a bath of boiling water. what is the partial pressures of neon and helium gas in the bottle?

Answer 1

The partial pressures of neon and helium in the bottle are calculated using the ideal gas law considering the temperature and the number of moles of each gas. The mass of helium is first converted to moles, and then the partial pressure of each gas is found in relation to the total pressure which, at the boiling point of water, is 1 atm.

Step-by-step explanation:

Calculating Partial Pressures of Neon and Helium

To answer the question of what the partial pressures of neon (Ne) and helium (He) gas in the bottle are, we need to apply the ideal gas law, which states that PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin. Given that the temperature is constant and the bottle is submerged in boiling water, we can assume the temperature is 100°C or 373 K since water boils at 100°C at standard atmospheric pressure.

Before we calculate the partial pressures, we convert the mass of helium to moles using the molar mass of helium (4.00 g/mol):
nHe = massHe / molar massHe = 12.0 g / 4.00 g/mol = 3.0 moles.

Now we use the total number of moles of each gas to determine their partial pressures:
Ptotal = PNe + PHe, and since the volume and temperature are constant, the partial pressures are proportional to the moles of gas.

To find Ne's partial pressure, we can set up the equation:
PNe = (nNe / (nNe + nHe)) × Ptotal

Given that the total pressure (Ptotal) inside a container at boiling water temperature is 1 atm, and knowing the moles of Ne and He, we can solve for PNe and PHe.