What is the pressure of BrF5 (g) at equilibrium when the following reaction occurs? (help)

Question

What is the pressure of BrF5 (g) at equilibrium when the following reaction occurs?

Br2 (g) 5F2 (g) ↔ 2BrF5 (g)

Kp = 4.00 x 107

Initial : 0.200 1.200 0.300

atm atm atm

A. 1.65 atm

B. 0.700 atm

C. 0.600 atm

D. 0.900 atm

E. 0.500 atm

please help

Answer 1

first,they are all gases.this translates mole to pressure.

second, Kp is verry high,without any calculation we know reaction

is total

third,F2 is in excess 0.2atm of Br2 needs 5 times fluorine,1atm

so,in the end there is:

0.3 atm BrF5 from the start

0.2 atm F2 excess

0.2 atm Br2+1 atm F2 gives (from 1+5 result 2 mole) 0.4 atm BrF5

total  BrF5 0.7atm B