Physical and Chemical Changes: Four Weddings and a FriendshipMultiple-Choice Questions

Select the most correct answer

1. An atom is:

(a) easily broken into smaller pieces

(b) a very very large particle

(c) the smallest piece of any element, which can exist in nature

(d) composed of molecules.

2. A molecule:

(a) consists of two or more atoms mixed together but not bonded

(b) consists of two or more electrons combined together

(c) consists of two or more ions joined together

(d) consists of two or more atoms joined together chemically.

3. A physical change:

(a) can be easily reversed

(b) always happen with gases

(c) is difficult to reverse

(d) makes something new and different.

4. A chemical change:

(a) can be easily reversed

(b) always occurs in gases

(c) changes water to steam

(d) makes something new and different.

5. All matter is composed of:

(a) gases

(b) solids

(c) atoms and/or molecules

(d) liquids.

6. Using water as an example, explain clearly, the difference between a physical and a chemical change.

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6. The formula for di-nitrogen tri-oxide is:

(a) NO3

(b) N2O

(c) N2O3

(d) N3O2

7. The two elements involved in the formation of di-nitrogen tri-oxide are:

(a) oxygen and hydrogen

(b) nitrogen and oxygen

(c) di-nitrogen and tri-oxygen

(d) nitrogen and hydrogen.

8. The changing of water to steam is an example of:

(a) a chemical reaction

(b) heating

(c) a physical change

(d) a chemical change.

9. Electrons are:

(a) tiny atoms, which play a part in chemical reactions

(b) tiny particles which makeup ions

(c) tiny particles, which play a part in chemical reactions

(d) found only in ions.

Longer Questions

10. Explain fully, the difference between an atom and an ion giving an example of a negative and positive ion to illustrate your answer.

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11. Using water as an example, explain clearly, the difference between a physical and a chemical change.

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12. Draw and fully label a simple diagram of a sodium atom and a chlorine atom and then explain why they combine together and what an ion is.

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13. Why do you think that the periodic table is important and useful to scientists?

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