Which of the following best describes salad dressing in terms of the classification of matter?

• A. Homogeneous mixture (solution)
• B. Heterogeneous mixture (suspension)
• C. Pure substance
• D. Colloid

Answer: (B)

Verified step by step guidance

1. Step 1: Understand the classification of matter into pure substances and mixtures. Pure substances have a uniform and definite composition, while mixtures contain two or more substances physically combined.
2. Step 2: Recognize that mixtures can be further classified as homogeneous or heterogeneous. Homogeneous mixtures (solutions) have a uniform composition throughout, while heterogeneous mixtures have visibly different parts or phases.
3. Step 3: Identify the types of heterogeneous mixtures: suspensions and colloids. Suspensions have larger particles that can settle out over time, while colloids have smaller particles that remain dispersed and do not settle.
4. Step 4: Consider the nature of salad dressing. Many salad dressings contain oil and vinegar, which do not mix uniformly and form separate layers or droplets, indicating visible differences in composition.
5. Step 5: Conclude that because salad dressing shows distinct phases and particles that can separate, it is best classified as a heterogeneous mixture, specifically a suspension.