Question

a sample of gas has a volume of 200. ml at 20.0°c. what will be its volume at 40.0°c, pressure remaining constant?
250 ml
200 ml
100 ml
214 ml

Explanation:

Step1: Convert temperatures to Kelvin

$T_1 = 20.0^\circ\text{C} + 273.15 = 293.15\ \text{K}$, $T_2 = 40.0^\circ\text{C} + 273.15 = 313.15\ \text{K}$

Step2: Apply Charles's Law $\frac{V_1}{T_1} = \frac{V_2}{T_2}$

Rearrange to $V_2 = V_1 \times \frac{T_2}{T_1} = 200\ \text{mL} \times \frac{313.15}{293.15}$

Step3: Calculate the result

$V_2 \approx 200 \times 1.068 \approx 213.6\ \text{mL} \approx 214\ \text{mL}$

Answer:

D. 214 ml