UNIT 9MATTER AND MATERIALS

INDEX1. VOCABULARY

2. WHAT IS MATTER?

3. MATTER STATES:3.1 SOLID3.2 LIQUID3.3 GAS

4. MATERIALSWHAT ARE MATERIALS?KIND OF MATERIALSMATERIALS PROPERTIES

5. RECYCLING

1. VOCABULARYA

Atom

B

Bend

C

Cloth

Concrete

Container

D

Dig

E

Environment

L

Leather

M

Matter

Molecules

P

Pottery

Preserve

R

Recover

Rubber

S

Steel

U

Useless

V

Volume

W

Weakness

2. WHAT IS MATTER?Matter is everything around you. Matter is formed by groups of atoms that form molecules. The atoms that are in the molecules stay linked because they share or change electrons.

Molecules are formed by 2 or more atoms of 1 or more elements. For example: a water molecule is formed by 2 atoms of hydrogen and 1 atom of oxygen.

ATOM MOLECULE

3. MATTER STATES3.1 SOLID

Solids have a defined shape and volume, molecules are so close together that they form a hard structure.

Examples: Wood, stone... EXPLANATION:When you take a stone, wood, plastic…and change it from one place to another, they don´t change size or shape. Shape and size of solids are the same as long as we don´t transform them by carving, cutting, hitting…

SOLID’S MOLECULESMolecules in solids are tightly together. They vibrate but they can´t move.

3. MATTER STATES3.2 LIQUID

Liquids fill up the shape of their containers. Liquids can flow into any container and change their shape, while they stay with the same volume.

Examples: Water, oil, milk, juice...EXPLANATION:When you pour water into a glass, the water gets the shape of the glass. If you change that water into a bowl, it gets the shape of the bowl. The amount of water doesn´t change, only the shape.

LIQUID’S MOLECULESMolecules in liquids are close together. They move and slide past each other.

3. MATTER STATES3.3 GAS

Gases don´t have a defined shape or volume. They take the shape and the size of their container. Gases are as big as their containers.

Examples: Hydrogen, oxygen...

EXPLANATION:Gases are all around us. They move and grow as long as they have space to do it.

GAS’ MOLECULESMolecules in gases are separated and free. They move around and vibrate at high speed.

3. MATTER STATESMATTER STATE CHANGES

SOLID

GAS

LIQUID

CONDENSATION

EVAPORATION

SOLIDIFICATION

MELTING

SUBL

IMAT

ION

3. MATTER STATES

http://www.youtube.com/watch?v=HAPc6JH85pM

http://www.youtube.com/watch?v=UnBoQe2rsgo

4. MATERIALS4.1 WHAT ARE MATERIALS?

Objects are made of matter. Matter that is used to make objects is called material.

Wood, plastic and glass are materials.

All these things are made out of wood.

4. MATERIALS4.2 KIND OF MATERIALS

Materials are classified into two main groups:

- Natural materials: Materials that are found around us. To take them we have to dig them out the ground, or take them from living things.

Examples: Wood, metal, stone...

- Artificial materials: Are natural materials transformed by humans in many different ways.

Examples: Oil can be changed into plastic, glass is made by heating sand...

4. MATERIALS4.3 MATTER PROPERTIES

Each material has different properties. These properties tell us what they are like, and how we can use them:

- Strength: the property of a material to support weight without breaking. Concrete and steel are strong, so they are used in construction.

- Flexibility: the property of bending without breaking down. Leather, paper and cloth are flexible materials.

- Elasticity: the property of recovering the shape after being deformed. Rubber is elastic, so it is used to do wheels.

- Weakness: the property of being easily broken down. Glass and pottery are weak materials.

5. RECYCLINGMaterials are used to do different kind of things. Sometimes when things are useless we throw them away, but it would be better to use them for something different.

Recycle: process that changes something so it can be used again.

Reuse: using something again without changing it.

Reduce: using less things as possible.

5. RECYCLINGRecycling is very important to preserve the environment. Plastic and metallic materials are very contaminant because nature takes a long time to degrade them. To recycle all these materials there are different containers for each kind of waste:

- Green for glass.

- Blue for paper.

- Black/grey for organic wastes.

- Yellow for plastics and cans.

GLASS

ORGANICWASTES

PLASTICANDCANS

PAPER