NTA Abhyas NEET2020ChemistryChemical KineticsPractice
The order of the gaseous reaction A g ⟶ 2 B g + C g is found to be one at the initial pressure P 0 = 90  torr . The total pressure after ten minutes is found to be 180  torr . Find the value of the rate constant ?
Options
- A1 .15 × 10 - 3 s - 1
- B2 .30 × 10 - 3   s - 1
- C3 .45 × 10 - 3   s - 1
- D4 .60 × 10 - 3 s - 1
Correct answer
A. 1 .15 × 10 - 3 s - 1
Step-by-step solution
Given, Initial pressure of A, P 0 = 90 torr Let's assume there is a decrease in pressure of A by P 0 torr after 10 mins. Therefore, after 10 mins the reaction mixture will look like, A g ⟶ 2 B g + C g P 0 − p 2 p p P t = P 0 + 2 p = 180 torr p = 45 torr Thus, after 10 mins, the pressure of A will be, P A = P 0 − p = 90 − 45 = 45 torr k = 1 t ln P 0 P A k = 1 600 ln 90 45 = 1.15 × 10 − 3 s − 1