1. According to the phase diagram for water, how is the state of water determined?
a. proceed up a vertical line at any given temperature
b. read the phase at the intersection of any given temperature and pressure
c. at a given pressure, proceed horizontally to the S-L or L-G line
2. Temperature is a direct measurement of the energy contained in a substance.
a. True
b. False
3. Why does an evaporating liquid cool down, according to the Kinetic Molecular Theory?
a. Heat is required to evaporate a liquid.
b. Heat is lost through elastic collisions.
c. The highest velocity molecules are lost.
d. Heat must be dissipated to break the liquid bonds.
1. The correct answer is b. According to the phase diagram for water, the state of water is determined by reading the phase at the intersection of any given temperature and pressure. The phase diagram shows the different phases of water (solid, liquid, and gas) at different combinations of temperature and pressure.
2. The correct answer is b. False. Temperature is not a direct measurement of the energy contained in a substance. Temperature is a measure of the average kinetic energy of the particles in a substance, but it doesn't directly represent the total energy contained in the substance. Other factors, such as the mass and specific heat of the substance, are also important in determining its total energy.
3. The correct answer is a. Heat is required to evaporate a liquid. According to the Kinetic Molecular Theory, when a liquid evaporates, some of its molecules gain enough energy to overcome the attractive forces between them and escape from the liquid surface as gas molecules. In order for these molecules to gain enough energy to evaporate, heat must be supplied to the liquid. As a result, the surrounding environment experiences a cooling effect.