Which equation expresses the relationship among pressure, volume, and temperature for a fixed amount of gas according to the ideal gas law?

Which equation expresses the relationship among pressure, volume, and temperature for a fixed amount of gas according to the ideal gas law?

• A. P + V = RT
• B. P V^2 = nRT
• C. PV = nRT
• D. PV = nRT^2

Answer: (C)

In the ideal gas law for a fixed amount of gas, the product of pressure and volume equals the gas constant times the amount of gas times temperature. This means PV is proportional to T, and the exact relationship is PV = nRT. The constant n is the number of moles and R is the gas constant (its value depends on the units used). If temperature increases with n and R fixed, either pressure or volume must increase to keep PV = nRT. In a rigid container (volume fixed), pressure rises linearly with temperature. If the volume can change (piston), pressure and volume adjust so that their product matches nRT. The other forms alter the dependence on temperature or introduce extra powers of V or T, which does not match the established linear relationship between PV and T in the ideal gas law.

In the ideal gas law for a fixed amount of gas, the product of pressure and volume equals the gas constant times the amount of gas times temperature. This means PV is proportional to T, and the exact relationship is PV = nRT. The constant n is the number of moles and R is the gas constant (its value depends on the units used).

If temperature increases with n and R fixed, either pressure or volume must increase to keep PV = nRT. In a rigid container (volume fixed), pressure rises linearly with temperature. If the volume can change (piston), pressure and volume adjust so that their product matches nRT.

The other forms alter the dependence on temperature or introduce extra powers of V or T, which does not match the established linear relationship between PV and T in the ideal gas law.