JEE Main 202628 JanuaryEvening Shift
- Exam
- JEE Main
- Year
- 2026
- Date
- 28 January
- Shift
- Evening Shift
- Subject
- Chemistry
- Chapter
- Chemical Equilibrium
JEE Main 2026 · 28 January · Evening Shift · Chemistry · Chemical Equilibrium
Observe the following equilibrium in a 1 L flask. A(~g)...
Observe the following equilibrium in a 1 L flask.
At , the equilibrium concentrations of A and B are 0.5 M and 0.375 M respectively. 0.1 moles of A is added into the flask and heated to to establish the equilibrium again. The new equilibrium concentrations (in M) of A and B are respectively
At , the equilibrium concentrations of A and B are 0.5 M and 0.375 M respectively. 0.1 moles of A is added into the flask and heated to to establish the equilibrium again. The new equilibrium concentrations (in M) of A and B are respectively
Options
- A.
- B.
- C.
- D.
Correct answer
C. .
Step-by-step solution
Initial equilibrium:
[A]=0.5 M, [B]=0.375 M;
After adding 0.1 mol A: [A]=0.6 M, [B]=0.375 M; Q=0.625
Q < Kc, so equilibrium shifts right.
Let x be A that decomposes:
0.375+x=0.45-0.75x
1.75x=0.075; x≈0.0429
New [A]=0.6-0.0429=0.557 M; [B]=0.375+0.0429=0.418 M
[A]=0.5 M, [B]=0.375 M;
After adding 0.1 mol A: [A]=0.6 M, [B]=0.375 M; Q=0.625
Q < Kc, so equilibrium shifts right.
Let x be A that decomposes:
0.375+x=0.45-0.75x
1.75x=0.075; x≈0.0429
New [A]=0.6-0.0429=0.557 M; [B]=0.375+0.0429=0.418 M