The volume of a fixed mass of gas is directly proportional to its
temperature if the pressure is kept constant.*
a. Boyle's law
b. Charles's law
c. gay-lucssac's law

Charles's law

Explanation:

Charles's law is one of the gas laws, and it explains the effect of temperature changes on the volume of a given mass of gas at a constant pressure. Usually, the volume of a gas decreases as the temperature decreases and increases as the temperature also increases.

Mathematically, Charles's law can be expressed as:

V ∝ T

V = kT or (V/T) = k

where v is volume, T is temperature in Kelvin, and a k is a constant.

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c. magnitude and direction