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QJEEM23Chf4ee: JEE Main 2023 Chemistry - Class 12 JEEM23Chf4ee Solution: A(g) 2B(g) + C(g) is a first order reaction. The initial…

A(g) →\to 2B(g) + C(g) is a first order reaction. The initial pressure of the system was found to be 800 mm Hg which increased to 1600 mm Hg after 10 min. The total pressure of the system after 30 min will be _________ mm Hg. (Nearest integer)

Step-by-Step Verified Solution

At 10 minutes, the pressure increased by 2x:

800+2x=1600800 + 2x = 1600

2x=8002x = 800

x=400x = 400

The rate constant (k) can be found as:

k=2.30310log⁡800400=2.303×log⁡210k = \frac{2.303}{10} \log \frac{800}{400} = \frac{2.303 \times \log 2}{10}

For 30 minutes, we can set up the equation:

k=2.30330log⁡800800−yk = \frac{2.303}{30} \log \frac{800}{800 - y}

2.303×log⁡210=2.30330log⁡(800800−y)\frac{2.303 \times \log 2}{10} = \frac{2.303}{30} \log \left(\frac{800}{800 - y}\right)

Solving for y:

(800800−y)=8\left(\frac{800}{800 - y}\right) = 8

800−y=100800 - y = 100

y=700y = 700

Now we can find the total pressure after 30 minutes:

Total pressure = (800 - y) + 2y + y

Total pressure = 100 + 1400 + 700

Total pressure = 2200 mm Hg

So, the total pressure of the system after 30 minutes is 2200 mm Hg.

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