The initial concentration of $\text{X}$ and $\text{Y}$ were $\text{2}$ and $\text{4}\text{mole/L}$ respectively. For the following equilibrium $\mathrm{X}+2\mathrm{Y}\rightleftharpoons \mathrm{ }\mathrm{Z}$ which of the following relationship among equilibrium concentrations of $\text{X,}\text{Y}$ and $\text{Z}$ is not feasible?

• A

  [X] < [Z]
• B

  [X] < [Y]
• Correct answer
  C

  [X] > [Y]
• D

  [Y] > [Z]

Solution

Now $\left[\text{X}\right]\text{>}\left[\text{Y}\right]$
$\left(2-\mathrm{a}\right)>\left(4-2\mathrm{a}\right)$
$\mathrm{a}>2$
which is not feasible.

Hence, the correct answer is option: 'C'.