3.2 g of oxygen gas is placed in a vessel of 10 litre at 1000 K so that 60% oxygen is dissociated to gaseous oxygen atoms. Assuming ideal gas nature, the final pressure at 1000 K is:

Options

A. 0.821 atm
B. 1.31 atm
C. 0.33 atm
D. 0.49 atm

Answer

B

Explanation

3.2 g of `O_(2)` No. of moles contain are `rArr (3.2)/(32)` = 0.1 mole of `O_(2)`
`O_(2) (g) rArr 20 (g)`
at `t = 0 " " 0.1`
at `t = t_(1) " " 0.1 - 0.1 xx (60)/(100) " " 2 xx 0.1 xx (60)/(100)`
0.04 moles 0.12 mole
Initial moles ni = 0.1 mole
Final moles nf = `0.04 + 0.12 = 0.16` moles
Volume = 10 lt. Temperature = 1000 k
Using ideal gas equation.
`PV = nRT " " P = (nRT)/(V) = (0.16 xx 0.0821 xx 1000)/(10)`
P = 1.31 atm