A group of students recorded the melting points of two substances in the data table. Substance Melting Point 10°C 1. 100°C Which substance has stronger intermolecular forces? O A. Substance #1 because it has a lower melting point, so the molecules have a strong attraction to one another. O B. Substance #2 because it has a higher melting point, so the molecules have a strong attraction to one another. O C. Substance #1 because it has a lower melting point, so the molecules have a weak attraction to one another. O D. Substance #2 because it has a higher melting point, so the molecules have a weak attraction to one another.

Elemental carbon has one gas phase, one liquid phase, and two different solid phases, as shown in the phase diagram: (a) On the phase diagram, label the gas and liquid regions. (b) Graphite is the most stable phase of carbon at normal conditions. On the phase diagram, label the graphite phase. (c) If graphite at normal conditions is heated to 2500 K while the pressure is increased to 1010 Pa, it is converted into diamond. Label the diamond phase. (d) Circle each triple point on the phase diagram. (e) In what phase does carbon exist at 5000 K and 108 Pa? (f) If the temperature of a sample of carbon increases from 3000 K to 5000 K at a constant pressure of 106 Pa, which phase transition occurs, if any?

Baking Explain why the baking instructions on a boxof cake mix are different for high and low elevations.Would you expect to have a longer or a shorter cookingtime at a high elevation?

Cooking oil floats on top of water. From this observation, what conclusions can you draw regarding the polarity or hydrogen-bonding ability of molecules found in cooking oil?

Heat is added to boiling water. Explain why the temperature of the boiling water does not change. What does change?

Cake mixes and other packaged foods that require cooking often contain special directions for use at high elevations. Typically these directions indicate that the food should be cooked longer above 5000ft. Explain why it takes longer to cook something at higher elevations.

Is it possible to liquefy nitrogen at room temperature (about 25 C)? Is it possible to liquefy sulfur dioxide at room temperature? Explain your answers.

Some water is placed in a sealed glass container connected to a vacuum pump (a device used to pump gases from a container), and the pump is turned on. The water appears to boil and then freezes. Explain these changes using the phase diagram for water. What would happen to the ice if the vacuum pump was left on indefinitely?