The gas law which describes the relationship between volume and temperature is

Step 1: Analyze the question The question asks which gas law links volume and temperature.

Step 2: Review each law

• Boyle's law: relates pressure and volume at constant temperature (P ∝ 1/V, so PV = constant).
• Charles' law: relates volume and temperature at constant pressure (V ∝ T, so V₁/T₁ = V₂/T₂).
• Dalton's law: the total pressure of a gas mixture equals the sum of the partial pressures of the individual gases.
• Graham's law: the rate of diffusion of a gas is inversely proportional to the square root of its density (or molar mass).

Step 3: Identify the match Charles' law states that, at constant pressure, the volume of a fixed mass of gas is directly proportional to its absolute temperature (in Kelvin).

V₁/T₁ = V₂/T₂

For example, if a gas has a volume of 2 dm³ at 300 K and is heated to 600 K at constant pressure, its volume doubles to 4 dm³.

Step 4: Answer The correct option is **B.

Tip: Remember the pairings:

• Boyle → Pressure and volume (both are "pressure-volume" law)
• Charles → Temperature and volume (think "Charles keeps it Cool or hot, changing size")

Also, always convert °C to Kelvin (K = °C + 273) before using Charles' law. This is a common place where marks are lost in WASSCE calculations.