I saw that this was posted earlier but i can't find the previous one with the answer. Please Help. I don't understand how to make this equation work
The total pressure in a flask containing air and ethanol at 257C is 878 mm Hg. The pressure of the air in the flask at 257C is 762 mm Hg. If the flask is immersed in a water bath at 450C, the total pressure is 980 mm Hg. The vapor pressure of ethanol at the new temperature is ??? mm Hg.
I found this although I don't think that's what you are looking for. I know that DrWLS qustioned how a water bath would be over 100 degrees C.
http://www.jiskha.com/display.cgi?id=1201887790
To find the vapor pressure of ethanol at the new temperature, we can use the information given about the total pressure in the flask at different temperatures.
First, we need to understand the concept of vapor pressure. Vapor pressure is the pressure exerted by the vapor (in this case, ethanol) above a liquid in a closed container when the liquid and vapor are in equilibrium. It is influenced by temperature, and as the temperature increases, so does the vapor pressure.
In this case, we are given the total pressure in the flask at two different temperatures: 878 mm Hg at 25°C and 980 mm Hg at 45°C. We also know the pressure of the air in the flask at 25°C is 762 mm Hg.
To find the vapor pressure of ethanol at the new temperature, we can use Dalton's Law of Partial Pressures. According to this law, the total pressure in a system is the sum of the partial pressures of each component.
To calculate the vapor pressure of ethanol at 45°C, we need to subtract the pressure of the air in the flask at 45°C from the total pressure in the flask at 45°C.
vapor pressure of ethanol at 45°C = total pressure at 45°C - pressure of air at 45°C
We already have the values for the total pressure and the pressure of the air, so let's substitute them into the equation:
vapor pressure of ethanol at 45°C = 980 mm Hg - 762 mm Hg
Now we can calculate to find the vapor pressure of ethanol at 45°C:
vapor pressure of ethanol at 45°C = 218 mm Hg
Therefore, the vapor pressure of ethanol at 45°C is 218 mm Hg.