Question

which of the following is an oxidation half - reaction?
o fe3+ + e- ----> fe2+
o sn2+ ----> sn4+ + 2e-
o cl2 + 2e- ----> 2cl-
o o2 + 4h+ + 4e- ----> 2h2o
1 pts
question 27
which of the following is a reduction half - reaction?
o zn ----> zn2+ + 2e-
o 2h+ + 2e- ----> h2
o na ----> na+ + e-
o no + 2h2o ----> n3- + 4h+ + 3e-

Explanation:

Oxidation is the loss of electrons. In the reaction $Sn^{2+}\longrightarrow Sn^{4+}+2e^{-}$, tin loses electrons, so it is an oxidation half - reaction. Reduction is the gain of electrons. In the reaction $2H^{+}+2e^{-}\longrightarrow H_{2}$, hydrogen ions gain electrons, so it is a reduction half - reaction.

Answer:

Question 1: Sn2+ ----> Sn4+ + 2e-
Question 2: 2H+ + 2e- ----> H2