We can use the boiling point elevation equation in order to determine the new boiling point once the salt has been added:

Since sodium chloride will form two ions for each molecule in solution, the value for the van't Hoff factor will be 2. In addition, the mass of the water in the solution will be 3 kilograms, which can be determined by using the density of water.

Since water boils at 100 degrees Celsius, this means that the final boiling point of the solution is 100.29 degrees Celsius.

Since the solute is nonvolatile, it does not have an additive vapor pressure, but it will lower the vapor pressure due to taking up surface space in the solution. Using Raoult's law, we can determine the new vapor pressure of the solution:

Here,  is the molar fraction of the water, and  is the original vapor pressure of the water. Since 3 moles of solute were added, water now makes up 80% of the moles in the solution:

Since both compounds are volatile, they will both contribute to the vapor pressure. Using the percentages of each compound in solution, we can determine the vapor pressure for the mixture:

Parts  and  of the equation represent the molar fractions of the compounds multiplied by the corresponding vapor pressures. Adding these together will equal the new vapor pressure of the solution:

When the enthalpy of a reaction is negative, it means that heat has been released from the system to the surroundings. This release of energy is referred to as an exothermic reaction.

Endothermic reactions have a net heat flow into the system. Exergonic and endergonic are terms used to describe the change in free energy for a given system.

A positive value for ΔG (Gibbs free energy) will guarantee a nonspontaneous reaction. When ΔH (enthalpy) is postive and ΔS (entropy) is negative, the change in Gibbs free energy must be positive and, therefore, nonspontaneous.

Because T (temperature) will always have a positive value, a negative entropy and positive enthalpy will always result in a positive Gibbs free energy.

All of the following scenarios would lead to spontaneous reaction, since each scenario would result in a negative Gibbs free energy (-ΔG).

Negative enthalpy, positive entropy:

Positive enthalpy and entropy with high temperature:

Negative enthalpy and entropy with low temperature:

According to the Gibbs free energy equation, a system is at equilibrium when  is equal to 0.

Since , a system is in equilibrium when               . A negative Gibbs free energy means that the reaction will be spontaneous. At equilibrium, the forward reaction rate equals the reverse reaction rate, though the net rate is zero.

There are six possible phase changes between the three phases of matter. Deposition describes the change from gas to solid, while sublimation describes the transition from solid to gas. Freezing (crystallization) is the transition from liquid to solid, while fusion (melting) is the transition from solid to liquid. Condensation is the transition from gas to liquid, while vaporization (boiling) is the transition from liquid to gas.

Boiling occurs when the vapor pressure exceeds the air pressure. There is no air pressure in a vacuum, so water at any temperature will boil in a vacuum.

A liquid will boil when its vapor pressure increases to match the pressure of its environment. By this logic, a liquid with a higher vapor pressure will be closer to boiling. Liquids with low boiling points thus have greater vapor pressures.

Of the given compounds, methylene chloride has the lowest boiling point, meaning it will also have the highest vapor pressure.