A sample of nitrogen gas was collected via water displacement. Since the nitrogen was collected via water displacement, the sample is saturated with water vapor. If the total pressure of the mixture at 21 °C is 1.16 atm, what is the partial pressure of nitrogen? The vapor pressure of water at 21 °C is 18.7 mmHg.
I set up an equation according to Dalton's Law of partial pressure ---> 1.16= P1+18.7
I keep getting the answer wrong and need help.
To solve this problem, you correctly set up an equation using Dalton's Law of partial pressure, which states that the total pressure of a gas mixture is the sum of the partial pressures of each gas in the mixture.
According to your equation, the total pressure of the mixture is 1.16 atm. However, there seems to be an error in setting up the equation. The partial pressure of nitrogen should be P1, while the vapor pressure of water should be added as a separate term.
Here's the corrected equation: 1.16 atm = P1 (partial pressure of nitrogen) + 18.7 mmHg (vapor pressure of water).
Before proceeding to find the value of P1, it's important to ensure that both pressures are in the same unit. Since the given partial pressure is in atm, let's convert the vapor pressure of water from mmHg to atm for consistency.
1 atm = 760 mmHg
Converting the vapor pressure of water: 18.7 mmHg * (1 atm / 760 mmHg) = 0.0246 atm (approximately)
Now, substitute the values back into the equation:
1.16 atm = P1 + 0.0246 atm
To isolate P1, subtract 0.0246 atm from both sides of the equation:
1.16 atm - 0.0246 atm = P1
Simplifying,
1.1354 atm = P1
Therefore, the partial pressure of nitrogen is approximately 1.1354 atm.