The vapor pressure of a liquid is a measure of how much vapor of a liquid sits in the air above the liquid in a closed container. So, for example, a steam room has a very high vapor pressure of water. Do you think a substance that has weaker forces between molecules would in general have a greater or lesser vapor pressure than a substance with stronger forces between the molecules? For example, compare isopropyl alcohol and water.

The heater element of a 120 v toaster is a 5.4 m length of nichrome wire, whose diameter is 0.48 mm. the resistivity of nichrome at the operating temperature of the toaster is 1.3 × 10-6 ω·m. the toaster is operated at a voltage of 120 v. (a) what is the power drawn by the toaster? (b) if the cost of electricity is 12 ¢ per kilowatt-hour, and it takes 2 minutes to toast bread, how much does it cost for toasted bread? (c) when the heater element is at room temperature, is the resistivity in the nichrome wire greater than, less than, or equal to it’s resistivity when at operating temperature? explain.