Distinguish between concentration acid and strong acid

Here's the distinction between concentrated acid and strong acid:

• A concentrated acid refers to an acid solution that contains a large amount of acid solute dissolved in a given volume of solvent (usually water). It describes the quantity of acid present. For example, a 12 M HCl solution is concentrated.

• A strong acid refers to an acid that ionizes almost completely in an aqueous solution, donating nearly all of its protons ($\text{H}^+$ ions) to water. It describes the extent of dissociation of the acid molecules. For example, hydrochloric acid ($\text{HCl}$) is a strong acid because it dissociates completely in water, regardless of its concentration.

The key difference is that concentration describes how much acid is present, while strength describes how much of that acid dissociates into ions. You can have a dilute strong acid (e.g., 0.01 M $\text{HCl}$) or a concentrated weak acid (e.g., 17 M acetic acid).