Write half-reactions for the oxidation and reduction process for each of the following.
a. fe2+ + mno4 - fe3+ + mn2+
b. sn2+ + io3 - sn4+ + i-
c. s2- + no3 - s + no
d. nh3 + no2 n2 + h2o

a) ⇒

    + 2 + 3⇒

b) ⇒

   ⇒

   ⇒

c)⇒

  ⇒

d) ⇒

   ⇒

Explanation:

a) ⇒

    + 2 + 3⇒ half reaction suggest that you need water to reaction occurs.

b) ⇒

   ⇒

   ⇒ half reaction suggest that you need acid to reaction acurrs.

c)⇒

  ⇒

d) ⇒

   ⇒ note that you can obtain the total reaction by miltiplying first half reaction by 4 and second half reaction by 3.

b. accuracy of the data matters alot more than its number of digits, organization or amount of detail. quantitative observation is more accepted than the qualitative observation.