Question

Gaseous iodine pentafluoride, IF5, can be prepared by the reaction of solid iodine and gaseous fluorine: I2(s)+5F2(g)→2IF5(g) A 4.60 −L flask containing 9.20 g I2 is charged with 9.20 g F2, and the reaction proceeds until one of the reagents is completely consumed. After the reaction is complete, the temperature in the flask is 125 ∘C.

Part A What is the partial pressure of IF5 in the flask?

Part B What is the mole fraction of IF5 in the flask?

Part C Draw the Lewis structure of IF5.

Part D What is the total mass of reactants and products in the flask?

Answer 1

a)

mol of I2= masS/MW = 9.2/253.809 = 0.03624 mol of I2

mol of F2 = mass/MW = 9.2/37.9968064 = 0.2421256 mol of F2

so..

expected ratio is 1:5

0.03624 mol of I2 --> 0.03624 *5 = 0.1812 mol of F2, we have 0.242 so this is in excess

mol of Fe left = 0.2421256 -0.1812 = 0.0609256 mol of F2

mol of IF5 formed =0.03624 *2 = 0.07248 mol of IF5

so..

at this conditions...

A)

P-IF5 = nRT/V = ( 0.07248 *0.082)(125+273)/(4.6) = 0.514 atm

B)

mol fraciton --> mol o fIF5/total mol = 0.07248 / (0.07248 +0.0609256 ) = 0.54710144927

C)

lewis structure for IF5

D)

total mass of reactants and product at end:

initial mass = 9.2+9.2 = 18.4 g

final mass = initial mass = 18.4 g