Final answer:
Sodium hydroxide is NOT a salt.
Step-by-step explanation:
A salt is a compound that is formed when an acid reacts with a base. It is made up of a cation (positive ion) and an anion (negative ion). In the options given, Sodium hydroxide is NOT a salt because it is a strong base, not an ionically bonded compound like the other options. Sodium chloride (NaCl), Sodium (Na), and Sodium nitrate (NaNO3) are all salts.
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