1. Determine whether the following reactions as oxidation or reduction.

\(Na\) ➝ \(Na^+\) + \(e^–\)
\(Fe_3{^+}\) + \(2^e{^–}\) ➝ \(Fe^+\)
 
A chemical reaction that involves adding oxygen or removing hydrogen or loss of electrons is called .
 
A chemical reaction involving adding hydrogen or removing oxygen, or gaining electrons is called .