Question

1. aluminum can be classified as a. an element b. a compound c. a mixture d. none of the above 8. tap - water can be classified as a. an element b. a compound c. a mixture d. none of the above e. all of the above 9. calcium carbonate can be classified as a. an element b. a compound c. a mixture d. none of the above 10. which would be an example of a homogenous mixture? a. vinegar b. only water c. table - salt d. sodium chloride e. aluminum 11. distillation is most useful for separating: a. a solid from a liquid b. two liquids with different boiling points c. a soluble solid from a solution d. insoluble particles from a liquid e. none of the above 12. which separation technique works best to separate sand from a liquid? a. evaporation b. filtration c. distillation d. extraction e. none of the above

Explanation:

1. Aluminum is an element. Tap - water is a mixture as it contains various substances dissolved in water. Calcium carbonate is a compound made of calcium, carbon and oxygen. A homogeneous mixture has a uniform composition throughout. Vinegar is a homogeneous mixture of acetic acid and water.
2. Distillation is used to separate two liquids with different boiling points.
3. Filtration is the best method to separate sand (insoluble solid) from a liquid as sand particles cannot pass through the filter paper while the liquid can.

Answer:

1. a. An element
2. c. Mixture
3. b. A compound
4. a. Vinegar
5. b. Two liquids with different boiling points
6. b. filtration