Question

How many electrons are needed to reduce N$_2$ to NH$_3$?

• A. 3
• B. 4
• C. 5
• D. 6

Hint:

Using a simple frame or just bolding for the box Key Points: Reduction involves a decrease in oxidation state (gain of electrons). Determine the oxidation state of the element in the reactant and product. Calculate the change in oxidation state per atom. Multiply the change per atom by the number of atoms of that element in the reactant molecule (N$_2$ has 2 N atoms) to find the total electrons transferred for the molecule. Oxidation State: N in N$_2$ = 0; N in NH$_3$ = -3.