Page 186 - Chemistry eBook
P. 186
Boiling Points of Four Liquids
Boiling points of Four Liquids at STP:
1. Propane: 55°C
2. Ethanol: 78°C
3. Water: 100°C
4. Ethanoic acid: 118°C
• Ethanol acid needs to reach the highest temperature to boil. This is because its
molecules have the strongest attraction to each other, so a lot of heat is needed to
break the bonds apart.
• This chart is based on standard atmospheric pressure (101.3 kPa)— the dotted line.
• If the pressure is lowered, the substance will boil at a lower temperature.
Water’s boiling point at standard pressure (101.3 kPa) is 100°C.
If the pressure is lowered to 80 kPa, water would boil at 95°C (a lower temperature). You can figure this out by drawing your own dotted line on Reffy at the vapor pressure of 80.
I could have figured all this out myself from Reffy.
185 © UNIT 5: MATTER
