Step-by-step explanation:
We can use the combined gas law to solve this problem, which relates the pressure, volume, and temperature of a gas:
(P₁V₁) / T₁ = (P₂V₂) / T₂
where P is the pressure, V is the volume, and T is the temperature.
We can assume that the pressure and amount of gas are constant, so we can simplify the equation to:
V₁ / T₁ = V₂ / T₂
Substituting the given values, we get:
3.50 L / 283.15 K = 3.99 L / T₂
Solving for T₂, we get:
T₂ = (3.99 L / 3.50 L) x 283.15 K
T₂ = 322.4 K
Therefore, the temperature of the gas at a volume of 3.99 L is approximately 322.4 K.