A flask of 1L having `NH_(3)(g)` at 2.0atm and 200K is connected with another flask of vol 800ml having HCl(g) at 8atm & 200K through tube of negligible volume. The two gases reacts to form `NH_(4)Cl(s)` with evolution of 43 KJ/mol heat. If heat capacity of at constant volume is 20J/K/mol and neglecting heat capacity of flask and solid, volume of solid formed and its pressure (R = 0.08).
The final pressure in the flask is

Options

A. 5.375KJ
B. 4.375KJ
C. 6.8KJ
D. 6.375J

Answer

A

Explanation

`NH_(3(g)) + HCl_((g)) rarr NH_(4)Cl_((s)), Delta H = - 43.0KJ`
`{:("Initial mole", (1 xx 2)/(0.08 xx 200), (8 xx 0.8)/(0.08 xx 200)0,0),(,= 0.125,=0.4,),("Final moles",0,0.275,0.125):}`
`:.` heat product = `0.125 xx 43 = 5.375 KJ`