Science (086) — AI-generated practice question

The notation (aq) means the substance is dissolved in water (aqueous solution). For example, NaCl(aq) indicates sodium chloride dissolved in water.

(l) denotes that the substance is in pure liquid form, not dissolved in any solvent. For example, H₂O(l) means liquid water itself.

Difference: (aq) = dissolved in water; (l) = pure liquid state.

Source: Chapter 1, Writing a Chemical Equation (physical states notation); Chapter 2, Acids-Bases

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• Examiners expect both notations to be defined clearly and a direct comparison made — that earns both marks.
• A common mistake is saying (l) means "liquid solution" — it strictly means the pure substance in liquid phase, not a solution.
• You can support with examples (e.g., HCl(aq) vs Br₂(l)) to make the distinction crisp.
• The source passages mention H⁺(aq) and OH⁻(aq) ions in solution, confirming (aq) = dissolved in water.