Chemistry Gases BUMHS 2022
PMDC Verified Question 43 of 65
The volume of a given mass of a gas according to Charle's law should be zero at:
A
-273°C
B
273°C
C
100°C
D
25°C
Tap any option to test your recall and reveal the step-by-step Propolis autopsy.

Propolis Cognitive Error Autopsy

Official Correct Choice:
Option A: -273°C
Concept:

Charles's Law states that the volume of a gas decreases by \( \frac{1}{273.15} \) of its volume at 0°C for every 1 degree Celsius drop in temperature.

Formula:

$$ V_t = V_o \left(1 + \frac{t}{273.15}\right) $$

Solution:

  • If we theoretically cool the gas down to -273.15°C (commonly rounded to -273°C), we substitute this into the equation:


  • \( V_t = V_o \left(1 - \frac{273}{273}\right) \).


  • \( V_t = V_o (1 - 1) = V_o(0) = 0 \).


  • At -273°C (Absolute Zero), the kinetic energy drops to zero, and the theoretical volume of the gas becomes zero (though in reality, the gas will liquefy long before reaching this point).


Why other options are incorrect:

  • Option B (273°C): At this high temperature, the volume would double compared to its volume at 0°C.
  • Options C & D: These are standard warm temperatures where gases occupy large volumes.

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