Which label belongs in the region marked X?
Chang makes the diagram below to compare Gay-Lussac's
law and Charles's law.
Gay-Lussac's Law Charles's Law
O involves changes in temperature
O has a constant volume
O shows an inversely proportional relationship
O does not involve pressure changes

A) involves changes in temperature

Explanation:

The figure is missing, but I assume that the region marked X represents the region in common between Gay-Lussac's law and Charle's Law.

Gay-Lussac's law states that:

"For an ideal gas kept at constant volume, the pressure of the gas is directly proportional to its absolute temperature"

Mathematically, it can be written as

where p is the pressure of the gas and T its absolute temperature.

Charle's Law states that:

"For an ideal gas kept at constant pressure, the volume of the gas is directly proportional to its absolute temperature"

Mathematically, it can be written as

where V is the volume of the gas and T its absolute temperature.

By looking at the two descriptions of the law, we see immediately that the property that they have in common is

A) involves changes in temperature

Since the temperature is NOT kept constant in the two laws.