UNIT 6: MATTER

  UNIT 6: MATTER

 

1.3 STATES OF MATTER

Matter has three different states: solid, liquid and gas.

-         Solids. They have a fixed volume and a fixed shape. In some cases we can change the shape of certain solid, for example a block of clay or plasticine.

-         Liquids. They have a fixed volume but they can change shape depending on the container they are in.

-         Gasses. They can change shape and volume. For example we can reduce the volume of gas if we compress it.

     2. MATTER CHANGES

2.1. TYPES OF CHANGES IN MATTER

Matter changes constantly and does not always stay the same. There are two types of changes:

-         Physical changes. This is when the composition of matter does not change. The size, shape, temperature can be different.

-         Chemical changes. This is when matter changes and creates a new substance.

2.2. PHYSICAL CHANGES

 There are two types:

-         Irreversible. This is when matter cannot go back to its original state. It   is permanent. For example:

When you cook an egg, The egg changes.

When you burn a piece of wood, you get ash.

-         Reversible. This is when matter can go back to its original state. It is not permanent. For example:

When you heat chocolate, it melts. When it cools, you get solid chocolate again.

When you mix salt and water, if you evaporate the water,   you can separate the salt and water.

VOCABULARY

To go back: volver

To burn: quemar

Wood: madera

Ash: ceniza

To heat:calentar

To melt: derretir

To cool: enfriar

To mix: mezclar

2.3. CHANGES OF STATE

The main changes of state are fusion, evaporation, condensation and solidification.

-         Fusion/Melting.  This is when a solid becomes a liquid.

-         Evaporation. This is when a liquid becomes a gas.

-         Condensation: This is when a gas becomes a liquid.

-         Solidification: This is when a liquid becomes a solid.

ACTIVITIES

1.-  How many types of changes do you know?

_______________________________________________________________ .

2.-  Complete the sentences.

- Evaporation is the change from ___________  to  ___________  state.

- Fusion is the change  from ___________ to ________________    state.

- Condensation is the change from ___________ to ___________ state.

- Solidification is the change from _____________ to __________ state.

 

3.- Name the changes of state and explain what they are.