Question

which graph correctly depicts the relationship between number of moles of gas and volume when pressure and temperature are constant?

Explanation:

Avogadro's Law states that at constant pressure and temperature, the volume (V) of a gas is directly proportional to the number of moles (n), i.e., \( V \propto n \). This means as moles increase, volume increases linearly, which matches the first graph (straight line with positive slope). The second graph shows inverse proportionality, and the third shows negative linearity, both incorrect.

Answer:

The first graph (straight line with positive slope) correctly depicts the relationship.