Answer to Question #320326 in General Chemistry for Rookie

Question

Answer the following questions based on YOUR OWN UNDERSTANDING. Please do not copy paste:(

1. The greater the molar heat of vaporization of a liquid, the greater its vapor pressure. Is this true or not? Explain why or why not.

2. As a liquid is heated at constant pressure, its temperature rises. This trend continues until the boiling point of the liquid is reached. No further rise in the temperature of the liquid can be induced by heating. Explain.

3. Why is molar heat of fusion lower than molar heat of vaporization?

Answer 1

1. It is false. Since with the greater the molar heat of vaporization of a liquid in the gas phase there are fewer particles, and therefore less vapor pressure.
2. The boiling point is the highest temperature at which a phase does not pass into another phase, or a liquid does not pass into a gas. An increase in temperature will lead to a change in the liquid-gas phase.
3. The heat of fusion is less than the heat of vaporization, since melting requires enough energy to move the molecules out of their places in the crystal lattice, leaving other molecular attractions intact. When evaporating, it is necessary to add enough energy to break almost all of the molecular gravity, as well as do the work of repulsing the atmosphere.