A student collects gas over water after reacting sodium bicarbonate with hydrochloric acid. The watwr in the collector is the same both inside and out. The partial pressure of the carbon dioxide gas collected is 740 atm.if the temperature at the time of the experiment is 25c what was the barometric pressure at the time of the experiment?
Ptotal = pCO2 + pH2O
Ptotal is what you want.
You know pCO2 is 740.
Look in your text/notes and find the vapor pressure of H2O at 25 c. That is the pH2O. Calculate Ptotal.
To determine the barometric pressure at the time of the experiment, we need to subtract the vapor pressure of water from the partial pressure of carbon dioxide gas. The vapor pressure of water can be obtained from a water vapor pressure table at a given temperature.
In this case, the temperature is 25°C (or 25 + 273 = 298 K). According to the water vapor pressure table, the vapor pressure of water at 25°C is approximately 23.8 mmHg.
Now, we need to convert the given partial pressure of carbon dioxide gas from atm to mmHg since the vapor pressure of water is in mmHg. To do this, we'll use the conversion factor: 1 atm = 760 mmHg.
Given partial pressure of carbon dioxide gas = 740 atm
Partial pressure of carbon dioxide gas in mmHg = 740 atm × 760 mmHg/atm = 561,440 mmHg
Finally, we can calculate the barometric pressure by subtracting the vapor pressure of water from the partial pressure of carbon dioxide gas:
Barometric pressure = Partial pressure of carbon dioxide gas - Vapor pressure of water
= 561,440 mmHg - 23.8 mmHg
≈ 561,416 mmHg
Therefore, the barometric pressure at the time of the experiment was approximately 561,416 mmHg.