Question

AB3 dissociated to form AB2 and B2 when the initial pressure of AB2 is 800 torr and the total pressure developed at eqilibrium is 900 torr.what is the fraction of AB3 dissociated

Answer 1

Answer:

¼ th in fraction or 25% of AB3 is dissociated.

Explanation:

We have the reaction as

AB₃(g) ↔️ AB₂(g) + ½ B₂(g)

The initial pressure = 800 torr

Now, after the equilibrium, the pressures will be  

At AB₃: 800 – α

At AB₂: α

At (½ B₂): α/2

Where α is the degree of dissociation

The total pressure at equilibrium is 900 torr

Therefore, we can write as  

(800 – α) + α + α/2 = 900

Or, α/2 = 100

Or, α = 200

Hence,  

The fraction of AB₃ dissociated will be  

= α / initial pressure

= 200 / 800  

= ¼

Also, the percentage of dissociation is ¼ * 100 = 25 %