Question 19

A water-based liquid preparation in which at least one ingredient has dissolved completely is called a solution.

A solution is a homogeneous mixture where one substance is completely dissolved in another, typically a solvent like water.

A) solution.

This option is correct because a solution is defined as a liquid mixture in which the solute (the dissolved substance) is uniformly distributed within the solvent. In this case, the context directly states that at least one ingredient has dissolved completely, which aligns perfectly with the definition of a solution.

B) suspension.

A suspension is a heterogeneous mixture where solid particles are dispersed in a liquid but not dissolved, meaning they can settle over time. Therefore, this option is incorrect as it does not fit the description of a preparation where ingredients are completely dissolved.

C) emulsion.

An emulsion is a mixture of two immiscible liquids, where one liquid contains a dispersion of the other. Since emulsions involve liquids that do not completely dissolve into each other, this option is not appropriate in the given context.

D) elixir.

An elixir is a type of liquid preparation that contains a dissolved substance, often including alcohol or other solvents, but it is not exclusively water-based and does not necessarily imply complete dissolution of all components. Thus, this option does not correctly answer the question.

Conclusion

The correct answer is clearly "solution," as it accurately describes a water-based preparation where at least one ingredient is fully dissolved. All other options fail to meet the criteria set in the question, highlighting the importance of complete dissolution in defining a solution.