NTA Abhyas JEE Main2020ChemistryChemical EquilibriumPractice
At 800 ° C , the following equilibrium is established as F 2 g ⇌ 2 F g The composition of equilibrium may be determined by measuring the rate of effusion of the mixture through a pin hole. It is found that 800 ° C and 1 atm mixture effuses 1 .6 times as fast as SO 2 effuses under the similar conditions. (At. wt. of F = 19 ). What is the value of K p (in atm) ?
Options
- A0.315
- B0.685
- C0.46
- D1.49
Correct answer
D. 1.49
Step-by-step solution
According to Graham's law of effusion r ∝ 1 M r mix r SO 2 = M SO 2 M mix ⇒ 2.56 = 6 4 M mix ⇒ M mixture = 2 5 Let mole fraction of F 2 is x. Therefore, mole fraction of F will be 1 − x 2 5 = 3 8 × x + 1 - x × 1 9 1 x = 0.315 ; ⇒ K p = P F 2 P F 2 = 0.685P 2 0.315P ≃ 1.49 atm