7B2 04 Compounds and reactions

7B2 04 Compounds and reactions

We are going to recap what we did last lesson.

Get ready to answer the questions on this presentation...

Multiple Choice

What is an element?

• An atom on its own

• A group of atoms

• A type of atom

• A molecule

An element...

• is a type of atom

• is in the periodic table

• can be found as an atom on its own

• can be found in molecules with other atoms

• Examples: carbon, sulphur, iron

Multiple Choice

What is a molecule?

• An atom

• Two or more atoms which are chemically joined together

• A compound

• Where all the atoms are the same

A molecule...

• Has more than one atom

• These atoms can be the same or different

• Examples: carbon dioxide (CO₂), molecular hydrogen (H₂), molecular oxygen (O₂)

Multiple Choice

What describes a compound?

• There is more than one different type of element

• There is more than one atom

• There is more than one different type of molecule

• There is only one atom

A compound...

• Contains more than one atom AND

• These atoms must be of different elements (types)

• The atoms must be chemically joined

• Such as carbon dioxide, water, but NOT molecular hydrogen or molecular oxygen (as these are the same elements, just joined up)

Remember, an atom is the smallest particle of matter we talk about.

Atoms can be arranged into solids, liquids, or gases (or plasma)

Did you say 'compound'? Oops!

Remember, a compound must have at least two atoms of different elements. It can't just have atoms of the same element (type).

A molecule can be either a compound (different elements) or not (same elements).

Now this is a compound!

• More than one atom - check! So we know it's a molecule...

• More than one element - check! So we know it's a compound!

Multiple Select

What are the particles in A?

• Molecules

• Compounds

• Atoms

• Matter

Molecules, compounds AND matter!

Molecule -Two or more atoms, chemically joined, and of the same or different types.

Compound - Two or more atoms, chemically joined, of different types

Matter - Anything that can be either a solid, liquid or a gas.

Multiple Choice

What is B?

• A compound

• A mixture

• An atom

• Molecules

It's a mixture!

Different molecules in the same space.

Multiple Choice

What is H?

• A mixture

• An atom

• A molecule

• A compound

It's a molecule and an element!

A molecule, because we can see they were all joined together, and an element, because there was only one type of atom present.