Pure and Impure Substances

1. ___________ are the smallest unit of an element that maintains the properties of that element.

• Atoms

• Elements

• Compounds

• mixtures

2. A/An _______________ is made up of one or more of the same kind of atom chemically combined.

• atom

• element

• compound

• molecule

3. A/an _____________ contains a variety of elements and compounds that are not chemically combined with each other.

• atom

• element

• compound

• mixture

4. A __________________ is a substance that has definite physical and chemical properties such as appearance, melting point, and reactivity.

• mixture

• pure substance

• compound

• element

5. True or False: elements and compounds are pure substances.

• True

• False

6. Elements are broadly classified as metals, nonmetals, and _________________.

• compounds

• mixtures

• metalloids

7. Coffee, mouthwash, and vinegar are examples of __________________ mixtures.

• heterogeneous

• homogeneous

• pure substances

8. Baking soda is the common name for sodium bicarbonate, or NaHCO3. It can be produced through chemical reactions involving carbon dioxide and sodium hydroxide. It is a

• pure substance

• mixture

9. Blood is a fluid found in the bodies of humans and other animals. It can be physically separated into plasma, red blood cells and white blood cells. Blood is a ___________________

• pure substance

• mixture

10. Ammonia is a colourless gas with the formula NH3. Ammonia contains hydrogen and nitrogen and cannot be broken down physically. Ammonia is a ___________________ .

• compound

• element