Which notation indicates that a substance is in aqueous solution?

Which notation indicates that a substance is in aqueous solution?

• A. (s)
• B. (aq)
• C. (g)
• D. (l)

Answer: (B)

The main idea here is how chemists label the physical state of a substance in a reaction. The symbol (aq) means the substance is in an aqueous solution—dissolved in water. That tells you the material isn’t a separate solid, liquid, or gas, but is dispersed as ions (or very well solvated molecules) in water. It’s the standard way to indicate a substance that has been dissolved, like table salt in water, written as NaCl(aq). In contrast, (s) means solid, (l) means liquid, and (g) means gas, so those indicate pure phases rather than dissolved ones. So, (aq) is the notation used whenever a substance is in water-based solution, distinguishing it from its pure solid, liquid, or gaseous forms.

The main idea here is how chemists label the physical state of a substance in a reaction. The symbol (aq) means the substance is in an aqueous solution—dissolved in water. That tells you the material isn’t a separate solid, liquid, or gas, but is dispersed as ions (or very well solvated molecules) in water. It’s the standard way to indicate a substance that has been dissolved, like table salt in water, written as NaCl(aq). In contrast, (s) means solid, (l) means liquid, and (g) means gas, so those indicate pure phases rather than dissolved ones.

So, (aq) is the notation used whenever a substance is in water-based solution, distinguishing it from its pure solid, liquid, or gaseous forms.