3º NS Unit 5 – MATTER AND ENERGY (Activity Book solutions)

HOMEWORK for the weekend:

1. Fisrt, check the solutions of the exercises in the books of N.S. (Student´s Book and Activity Book).

2. Then, do the TEST.

UNIT 5 Natural Science – MATTER AND ENERGY

3º NS ACTIVITY BOOK (solutions)

PAGES 26, 27

SOLUTIONS

1- a. matter ; b. materials

2- b. plastic / flexible / waterproof ; c. fabric / flexible / absorbent; d. glass / rigid / waterproof

3- A flexible material (can change shape easily). A rigid material (does not change shape easily). A resistant material (is difficult to break).

4- MELTING (solid / +heat / liquid) FREEZING (liquid / -heat / solid) EVAPORATION (liquid / +heat / gas)

PAGE 28

SOLUTIONS

5- a. do not have / do not have; b. do not have / have; c. have / have

6- Something which contains two or more types of matter. Answer: mixture.

7- a. Sieving is used for separating solids of different sizes.

b. Filtering is used for separating solids and liquids.

c. Evaporating is used for separating a solid dissolved in a liquid.

8- Evaporating – Filtering – Sieving.

PAGE 29

SOLUTIONS

9- Light energy – Electrical energy – Kinetic energy – Sound energy – Electrical energy – Thermal energy.

10- b. Electrical insulator ; c. Electrical insulator ; d. Electrical conductor.

PAGE 31

SOLUTIONS

1- c. no ; d. no ; e. no ; f. no ; g. yes ; h; yes ; i. no.