Question:

The R.M.S. speed of oxygen molecules at \(27^\circ\text{C}\) is \(v\). At \(927^\circ\text{C}\), its R.M.S. speed will be

Show Hint

R.M.S. speed depends on absolute temperature as \(v_{\text{rms}}\propto \sqrt{T}\).
  • \(v\)
  • \(\frac{v}{2}\)
  • \(2v\)
  • \(4v\)
Show Solution
collegedunia
Verified By Collegedunia

The Correct Option is C

Solution and Explanation

Concept: R.M.S. speed of gas molecules is proportional to the square root of absolute temperature: \[ v_{\text{rms}}\propto \sqrt{T} \]

Step 1:
Convert temperatures into kelvin. Initial temperature: \[ T_1=27^\circ\text{C}=27+273=300\ \text{K} \] Final temperature: \[ T_2=927^\circ\text{C}=927+273=1200\ \text{K} \]

Step 2:
Use proportionality: \[ \frac{v_2}{v_1}=\sqrt{\frac{T_2}{T_1}} \] \[ \frac{v_2}{v}=\sqrt{\frac{1200}{300}} \] \[ \frac{v_2}{v}=\sqrt{4} \] \[ \frac{v_2}{v}=2 \] \[ v_2=2v \] Therefore, \[ \boxed{2v} \]
Was this answer helpful?
0
0