Question

For the reaction
`2A(g)+B(g) hArr 3C(g)+4D(g)` ,brgt Two moles each of A and B were taken into a 1L flask. The following must always be true when the system attained equilibrium
A. `[A]=[B]`
B. `[A] lt [B]`
C. `[B] = [C ]`
D. `[A] +[B] lt[C ] +[D]`

Answer 1

Correct Answer - B
From the equation, it is clear that 2 moles of A combine with one mole of B. Let at equilibrium a moles of B have reactged. This means that 2a moles of A have reacted.
`:. `Equilibrium concentration of `A=2-2a`
Equilibrium concentration of `B=2-a`
Hence `[A] lt[B]`