Definition

An ion that has a charge opposite to another ion in a solution or electrochemical system.

Example

In the solution, the sodium ions acted as counterions to the negatively charged chloride ions.

Conversation

Hey, do you remember our chemistry class when we talked about counterions?

Yeah, I found that part really interesting!

Right? I never realized how important a counterion is in balancing charges.

Totally! It makes a big difference in chemical reactions.

Synonyms & Antonyms

Root Explanation

Counterion → It is formed from "counter-" (meaning opposite or against) and "ion" (from Greek "ion", meaning going or to go). The term refers to an ion that is opposite in charge to another ion, balancing the overall charge in a solution.

Memory Tip

Think of 'counter-' meaning opposite, and 'ion' meaning something that goes or moves. This helps you remember that a counterion is an ion that moves in opposition to another ion.

Visually Confused Words