What mass of zinc metal will be oxidized if #15.0*g# of #FeI_3# react to give iron metal?

1 Answer
Jun 5, 2017

Answer:

Approx. #4*g# zinc will be oxidized

Explanation:

Zinc is higher on the activity series than iron; it should therefore reduce the iron salt:

i.e. #stackrel(0)Zn(s) rarr Zn^(2+) + 2e^(-)# #(i)#

And for every oxidation there is a corresponding reduction..........

i.e. #Fe^(3+) + 3e^(-)rarrstackrel(0)Fe(s)# #(ii)#

We cross multiply: #2xx(ii) + 3xx(i):#

#3Zn(s) +2Fe^(3+) rarr 3Zn^(2+) + 2Fe(s)#

Both mass and charge are conserved, so this is a valid representation..........

We has #(15.0*g)/(399.88*g*mol^-1)=0.0375*mol# ferric salt.........and given the stoichiometry this will oxidize..........

#3/2xx0.0375*molxx65.39*g*mol^-1=??*g# zinc metal.......