Give the classification of matter when two substances are present with heteroatomic molecules.
a) heterogeneous mixture
b) homogeneous mixture
c) compound
d) element
The correct answer and explanation is :
Correct Answer:
a) Heterogeneous mixture
Explanation:
To classify matter properly, let’s break down the key terms in the question:
1. Matter Classification Overview
Matter can generally be categorized into:
- Pure substances (elements and compounds)
- Mixtures (homogeneous and heterogeneous)
2. Pure Substances vs. Mixtures
- Pure substances have a fixed composition and can either be:
- Elements: Consist of only one type of atom (e.g., O₂, Fe).
- Compounds: Consist of two or more different atoms chemically bonded together (e.g., H₂O, CO₂).
- Mixtures involve two or more substances physically combined. These can be:
- Homogeneous mixtures (solutions): Uniform composition throughout (e.g., saltwater, air).
- Heterogeneous mixtures: Non-uniform composition with visibly distinct phases or components (e.g., sand and water, salad).
3. Understanding “Heteroatomic Molecules”
A heteroatomic molecule consists of different types of atoms bonded together, which means it is a compound (e.g., CO₂, H₂O). The question specifically mentions two substances with heteroatomic molecules being present, indicating the presence of more than one compound.
4. Determining the Correct Classification
Since two different substances (both being compounds) are physically combined:
- If they form a uniform mixture (e.g., ethanol and water), it would be a homogeneous mixture.
- If the mixture has a non-uniform composition where the compounds remain distinct (e.g., oil and water), it is considered a heterogeneous mixture.
The key phrase “two substances” suggests that these heteroatomic molecules are not chemically bonded together but are instead mixed. If their composition isn’t uniform or they maintain separate phases, the most fitting classification is a heterogeneous mixture.
5. Why Other Options Are Incorrect
- b) Homogeneous mixture: Would apply if the mixture was completely uniform.
- c) Compound: Only applicable if a single type of heteroatomic molecule is present.
- d) Element: Incorrect because heteroatomic molecules involve multiple atom types.
Thus, when two different compounds are present and maintain distinguishable phases, the matter is best classified as a heterogeneous mixture.