Liquid vs Aqueous
A liquid is a state of matter. There being three states of matter, namely, solid, liquid, and gas. They all have their particular features and properties. By “aqueous,” we actually mean a solution where the solvent is water and some compound is dissolved in it.
Liquids
Liquidity is a state of matter. It has some typical characteristics which distinguish it from solids and gases. The first feature of liquid is that it can flow. Pour a glass of water at a slanting surface, and one can see it flowing from the higher to the lower surface. The second main feature is that it takes the shape of a container. When a liquid is poured into different shapes of containers, they take the shape of each container. When sealed in a container, they apply pressure evenly at all surfaces. The third most distinctive characteristic of liquids is the surface tension. The best example of surface tension is boiling milk in a container. Once it is boiled, it reaches the top and fluffs up like a fuzzy ball but does not immediately flow out. This characteristics leads to the phenomena called “wetting.”
Other features of liquids are that compression is resisted by some liquids while others don’t resist. In fluid dynamics, liquids are considered incompressible. The density of liquids is higher than gases and closer to solids because of the density. Liquids along with solids are called “condensed matter.” It is called “fluid” because of its capacity to flow similar to that of gases.
Liquids are measured in “volume” units. The units used are cubic meter (m.), cubic decimeter or liter, and cubic centimeter or milliliter.
1dm3=1L=0.001m3 or 1cm3=1mL=0.001L=10-6m3
The volume of liquids change with temperature and pressure. When heated they expand; when cooled they contract.
Aqueous solutions
Aqueous or aqueous solution is basically a solution where water is the solvent. “Aqueous” means “similar to,” “related to,” or “dissolved in water.” There are two types of substances, one which easily dissolves in water, called “hydrophilic,” and those which do not dissolve well in water, called “hydrophobic.” An example of an aqueous solution is, NaCl (aq) – this is a solution of sodium chloride in water. As seen in the example, (aq) refers to the aqueous solution in a chemical formula. Had it been in a molten state, NaCl would have been written as NaCl(l).
Substances which dissolve in water are called “soluble,” and those which do not are called “insoluble” and form a “precipitate” instead of an aqueous solution.
Aqueous solutions have either strong or weak electrolytes according to whether they conduct electricity or become poor conductors. Those which are good conductors have more ionization in the solution.
For understanding reactions between two aqueous solutions, calculations are based on the “concentration” of a solute’s prior form before dissolving and “polarity” of the solutions.
Summary:
The main and basic difference between an aqueous solution and liquids is that a liquid is a state of matter which has some typical characteristics which distinguishes it from other states of matter, i.e., solids and gases; whereas an aqueous solution is a solution where the solvent is water, which is a liquid, and some other substance or compound which is dissolved in it called the solute.