MATTER

What is matter?

Matter is everything we can see, smell or touch. Air, rocks and wood are all matter

Matter makes up all the objects that surround us.

All matter has properties: mass, volume and density



                                                MASS                                         VOLUME

Density is mass per volume. To calculate density, we divide the mass of an object or a subtance by its volume.

TYPES OF MATTER

Objects can be made of different types of matter

CHANGES IN MATTER

There are 2 types of change in matter:

1. Physical changes: the object or subtances change, but the matter remains the same. When water freezes, it is still water.

• Movement: the object changes position.
• Expansion: the temperature increases and the object gets bigger. (mercury in a thermometer)
• Contraction: the temperature decreases and the object gets smaller. (If a balloon is put in a fridge the air contracts and the balloon gets smaller)
• Changes of states: when the temperature rises, the states changes. (If water is heated, it changes into steam.)
• Fragmentation: the object is divided into small pieces. (If a glass breaks, the pieces are still made of glass.)

2. Chemical changes.

• Oxidation: One subtance changes into another when it reacts with oxigen. (Iron changes into rust)
• Combustion: When an object or subtance is burried, it changes into another substance. (when wood burns, it changes into ashes and gases)
• Putrefaction: This occurs when a living thing decomposes. (when an apple decays, its appearance, colour, smell and taste changes)

States of matter

Matter has 3 states:

Solids have their own shape.

Liquids don't have their own specific shape. They have the shape of the container which holds them.

Gases don't have a specific shape. They expand.

Matter can change from one state to another when temperature changes.

• Melting: a solid changes into a liquid.
• Solidification: a liquid changes into a solid.
• Boiling: a liquid changes into a gas.
• Evaporation: a liquid changes into a gas.
• Condensation: a gas changes into a liquid.
• Sublimation: a solid changes into a gas.

Matter can be classified into:

           mixtures    and      pure subtances

Pure subtances are made up of one single component.

Mixtures are made up of different component. In some mixtures we can distinguish the components.

Activities

Activity 1: Changing states

Activity 2: Gases around us

Activity 3: Solids and liquids

States of Matter millionaire game