Matter

Matter is

• everyone around us.

• everything around us.

• everything that can change physically only.

• everything that can change chemically.

When we cook...

• it's a natural event.

• we cause chemical changes only.

• we cause physical changes only.

• we provoke chemical and physical changes in matter.

Changes in air temperature and air pressure are...

• examples of changes provoked by natural events.

• examples of human changes.

• examples of solid changes.

• very healthy for matter.

When matter changes chemically,

• a new substance is created

• the properties of the new substance may be different from the properties in the original substance.

• all the options are correct.

• one or more substances may change into a new substance.

REFLECTION is impossible with gasses because...

• they expand a lot.

• they don't occupy a fixed volume.

• they are transparent.

• they can change physically.

Reflection is more regular if...

• it hits a smooth surface.

• the gas expands.

• on liquids only.

• it hits a rough surface.

Electricity is produced when...

• when a proton changes into a neutron.

• the nucleus of an atom expands.

• when matter becomes positively charged.

• an electron moves from one atom to another.

When an atom gains electrons,

• it is heavier than before.

• it becomes positively charged.

• it becomes negatively charged.

• it moves faster.

Mixtures are

• substances created from 2 or more types of matter.

• can be separated into its original components.

• homogeneous or heterogeneous.

• combinations of solids only.

An example of heterogenous mixture is...

• a pizza.

• seawater.

• a milkshake.

• the air.