Chemical and Physical Changes: MCQ/ Fill in the blanks/ Short questions answer

Fill In the blanks
1. _______________ changes produce new substances, with new
properties.
2. The Law of _______________ of Mass states that matter cannot be
created or destroyed.
3. _______________ is the process of a solid changing directly to a gas,
without passing through the liquid phase.
4. _______________ changes do not result in the production of new
substances.
5. Melting is an example of a change-of- _______________ operation.

MCQ

6. Which of the following is not an example of a physical change?
a) breaking glass c) cutting wood
b) melting gold d) burning wood

7. Which of the following represents matter in a solid form?
a) CO2(g) b) H2O(s) c) CCl4(l) d) O2(g)

8. Which of the following correctly represents the process of
sublimation?
a) CO2(g) --> CO2(s) c) CO2(g) -->CO2(l)
b) CO2(s) --> CO2(g) d) CO2(l) --> CO2(s)

Short questions


9. Explain how physical changes differ from chemical changes.
10. Does dissolving sugar in water represent a physical change or a chemical change? Explain your answer.

Answer Key

1. [chemical]—Chemical changes, which are also called chemical reactions,
result in the production of new substances, with their own properties.
2. [conservation]—The Law of Conservation of Mass is very important to the
study of chemistry.
3. [sublimation]—Dry ice is called “dry” because it never melts into the liquid
phase.
4. [physical]—If I cut a wooden board in two pieces, both pieces are still made
of wood.
5. [state or phase]
6. [D. burning wood]—If we completely burn a piece of wood in a fire, we
won’t have wood anymore.
7. [B. H2O(s)]
8. [B. CO2(s)
--> CO2(g)]
9. [Physical changes don’t result in the production of a new substance;
chemical changes do.]

10. [physical change; Dissolving sugar in water does not result in the production
of a new substance so it represents a physical change. The sugar can be
recovered through evaporation, which is a physical process.]