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A 1277 mL sample of nitrogen (N2) was collected by displacement of water at 24 degrees C under a total barometric pressure of 966 torr. What mass of dry nitrogen was collected? The vapor pressure of water at 24 degrees C is 22 torr.

Answer in units of g

1.59g

To find the mass of dry nitrogen collected, we need to consider the partial pressure of nitrogen and the molar mass of nitrogen.

First, let's determine the partial pressure of nitrogen (N2) using Dalton's law of partial pressures. Dalton's law states that the total pressure is the sum of the partial pressures of each gas present.

The total pressure is given as 966 torr, and the vapor pressure of water is 22 torr. So, the partial pressure of nitrogen can be calculated by subtracting the vapor pressure of water from the total pressure:

Partial pressure of nitrogen = Total pressure - Vapor pressure of water
= 966 torr - 22 torr
= 944 torr

Now, we need to convert the volume of nitrogen collected (1277 mL) to moles using the ideal gas law. The ideal gas law equation is:

PV = nRT

Where:
P = pressure in atm
V = volume in liters
n = number of moles
R = ideal gas constant (0.0821 L·atm/mol·K)
T = temperature in Kelvin

First, convert the temperature from Celsius to Kelvin:
T(K) = T(°C) + 273.15
= 24°C + 273.15
= 297.15 K

Next, convert the volume from milliliters (mL) to liters (L):
V(L) = V(mL) / 1000
= 1277 mL / 1000
= 1.277 L

Now, we can rearrange the ideal gas law equation to solve for moles (n):
n = PV / RT

Substituting the known values:
n = (944 torr) * (1.277 L) / (0.0821 L·atm/mol·K) * (297.15 K)
≈ 40.05 moles

Finally, calculate the mass of dry nitrogen using the molar mass of nitrogen (28.0134 g/mol):
Mass of dry nitrogen = moles of nitrogen * molar mass of nitrogen
≈ 40.05 moles * 28.0134 g/mol
≈ 1121.207 g

Therefore, the mass of dry nitrogen collected is approximately 1121.207 g.

Use PV = nRT and calculate n.

P in torr wet H2 = 966 torr
P H2O torr = 22 torr
PH2 dry = 966-22 = ?
PH2 in atm = ?/760

V = 1.277 L
n = unknown--Solve for this.
R = 0.08206 L*atm/mol*K
T = 297K

Find n, then n = grams/molar mass. You know n and molar mass, solve for grams.

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