Choose the best description of decolorizing carbon (charcoal) in this experiment. A Reactant B Solvent C Product D Insoluble impurity E Soluble impurity
The correct answer and explanation is:
Correct Answer: D) Insoluble impurity
Explanation:
In chemistry experiments, decolorizing carbon (also known as activated charcoal) is often used to remove colored impurities from a solution without reacting with the substances involved. To choose the best description from the given options, we need to understand what decolorizing carbon does in a typical experiment:
What Is Decolorizing Carbon?
Decolorizing carbon or activated charcoal is a highly porous form of carbon with a large surface area. It is not reactive under normal conditions but adsorbs (not absorbs) impurities, particularly colored organic compounds, onto its surface. This is especially helpful during the purification of organic compounds, such as in recrystallization.
Why the Correct Answer is “D) Insoluble Impurity”:
- Not a Reactant (A) – Activated charcoal does not chemically react with the substances in the experiment.
- Not a Solvent (B) – It is a solid, not a liquid; thus, it cannot dissolve other substances.
- Not a Product (C) – The experiment’s goal is not to produce charcoal or convert anything into charcoal.
- Not a Soluble Impurity (E) – Charcoal does not dissolve in the solvent; it remains solid and must be filtered out.
- ✅ Insoluble Impurity (D) – This is the best fit because charcoal stays suspended in the solution and is later removed by filtration. It carries adsorbed colored impurities with it, thus helping to clarify or “decolorize” the solution.
Summary:
Decolorizing carbon is best described as an insoluble impurity because it remains in the solid phase, does not dissolve or react, and is removed after it adsorbs unwanted colored substances. Its role is purely physical — to purify the solution without chemically altering the components.