I have the following question: A $100$ ml sealed flask with $60$ ml acetonitrile is heated to $140^\circ \pu{C}$. The boiling point of acetonitrile is $82^\circ \pu{C}$. What will be the pressure in the flask?

1. I understand I can use the Antoine equation, $\log{P} = A-B/(C+Temp)$, to calculate the vapor pressure of acetonitrile, but that equation only applies if there is some liquid acetonitrile left in the flask. How do I know if this is the case, or instead all acetonitrile has boiled and is in the vapor phase?

2. The total pressure is the sum of the partial pressures of acetonitrile and air. I can calculate the air pressure inside the flask with the ideal gas law, PV=nRT. However, I'm not sure what is the volume? Is it the total volume minus the acetonitrile volume ($100 - 60 = 40$ ml), or is it $40$ ml + $x$ ml, where $x$ is the additional volume due to the conversion of liquid acetonitrile into vapor?

Any ideas are welcome.

I have the following question:

A $100\ \mathrm{ml}$ sealed flask with $60\ \mathrm{ml}$ acetonitrile is heated to $140\ \mathrm{^\circ C}$. The boiling point of acetonitrile is $82\ \mathrm{^\circ C}$. What will be the pressure in the flask?

1. I understand I can use the Antoine equation, $\log{p} = A-B/(C+T)$, to calculate the vapor pressure of acetonitrile, but that equation only applies if there is some liquid acetonitrile left in the flask. How do I know if this is the case, or instead all acetonitrile has boiled and is in the vapor phase?

2. The total pressure is the sum of the partial pressures of acetonitrile and air. I can calculate the air pressure inside the flask with the ideal gas law, PV=nRT. However, I'm not sure what is the volume? Is it the total volume minus the acetonitrile volume ($100\ \mathrm{ml}-60\ \mathrm{ml}=40\ \mathrm{ml}$), or is it $40\ \mathrm{ml}+x$, where $x$ is the additional volume due to the conversion of liquid acetonitrile into vapor?

Any ideas are welcome.

I have the following question: A 100 ml sealed flask with 60 ml acetonitrile is heated to 140 °C. The boiling point of acetonitrile is 82 °C. What will be the pressure in the flask?

1. I understand I can use the Antoine equation, log (P) = A-B/(C+Temp), to calculate the vapor pressure of acetonitrile, but that equation only applies if there is some liquid acetonitrile left in the flask. How do I know if this is the case, or instead all acetonitrile has boiled and is in the vapor phase?

2. The total pressure is the sum of the partial pressures of acetonitrile and air. I can calculate the air pressure inside the flask with the ideal gas law, PV=nRT. However, I'm not sure what is the volume? Is it the total volume minus the acetonitrile volume (100 - 60 = 40 ml), or is it 40 ml + x ml, where x is the additional volume due to the conversion of liquid acetonitrile into vapor?

Any ideas are welcome.

I have the following question: A $100$ ml sealed flask with $60$ ml acetonitrile is heated to $140^\circ \pu{C}$. The boiling point of acetonitrile is $82^\circ \pu{C}$. What will be the pressure in the flask?

1. I understand I can use the Antoine equation, $\log{P} = A-B/(C+Temp)$, to calculate the vapor pressure of acetonitrile, but that equation only applies if there is some liquid acetonitrile left in the flask. How do I know if this is the case, or instead all acetonitrile has boiled and is in the vapor phase?

2. The total pressure is the sum of the partial pressures of acetonitrile and air. I can calculate the air pressure inside the flask with the ideal gas law, PV=nRT. However, I'm not sure what is the volume? Is it the total volume minus the acetonitrile volume ($100 - 60 = 40$ ml), or is it $40$ ml + $x$ ml, where $x$ is the additional volume due to the conversion of liquid acetonitrile into vapor?

Any ideas are welcome.