What are the reduced components in this reaction? Zn + 2H(+) → Zn(2+) + H2

1 Answer
Jun 25, 2014

The reduced component is H₂.

We use oxidation numbers to identify oxidation and reduction products.

For this question, two rules are important:

  1. The oxidation number of an element is zero.
  2. The oxidation number of an ion is the same as its charge.

In the equation

Zn + 2H⁺ → Zn²⁺ + H₂

the oxidation numbers are

Zn = 0 (Rule 1)
H⁺ = +1 (Rule 2)
Zn²⁺ = +2 (Rule 2)
H₂ = 0 (Rule 1)

We see that the oxidation number of H has changed from +1 in H⁺ to 0 in H₂. This is a reduction of oxidation number.

Reduction is a decrease in oxidation number.

Thus, H⁺ has been reduced to H₂, and H₂ is the reduction product.

Hope this helps.