Multiple choice

10 ml mixture of $CO, CH_{4}$ and $N_{2}$, exploded with an excess of oxygen, gave a contraction of 6.5 ml. There was a further contraction of 7ml when the residual gas was treated with $KOH$. Volume of $CO, CH_{4}$ and $N_{2}$ respectively, is :

  1. 5ml, 2ml, 3ml

  2. 2ml, 6ml, 4ml

  3. 1ml, 8ml, 9ml

  4. 4ml, 3ml, 5ml

Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

CO + 0.5 O2 -> CO2 (contraction 0.5 vol). CH4 + 2 O2 -> CO2 + 2 H2O (contraction 2 vol). N2 is inert. Let x, y, z be volumes of CO, CH4, N2. x+y+z=10. 0.5x + 2y = 6.5. x+y=7 (from KOH absorption of CO2). Solving: x=5, y=2, z=3.