What’s the MATTER? Chemistry is the study of the properties of matter and how matter

changes

Earth ChemistryChapter 4 Section 1

Matter

Matter

• Anything that has mass and takes up space.

• It is the “stuff” around us.• List 3 examples of Matter.

Properties of Matter

• Properties and changes of any type of matter depend on its make up.

• A pure substance is a single kind of matter.–Meaning it has a specific set of

properties.

• Which is pure? salt or blueberry muffins

Every form of matter has two kinds of properties

physicaland

chemical.

Look at the rock being passed around:

• Write a list of physical properties

• Write a list of chemical properties

Physical Properties

• Things that describe an object are physical.

• Physical properties can be observed and measured without changing the identity of the matter.

• Examples include: color, hardness, freezing & boiling point, state (solid/liquid/gas), solubility, density, ability to conduct electric current etc.

Chemical Properties

• Chemical properties describe a substance based on its ability to change into a new substance with different properties.– Example: wood burns to form ash and smoke

• Requires basic knowledge about particles and the substances they make up

• Not as easy to observe• Examples of chemical properties:

flammability and reactivity

Q: What is matter made up of?

• Each element can be identified by its specific physical and chemical properties.

• Element - a pure substance that cannot be broken down into any other substances by chemical or physical means. This is the simplest SUBSTANCE.

A: elements

More than 90 elements naturally occur on Earth.

Elements consist of ATOMS

• An atom is the smallest unit of an element.

– same chemical and physical properties

THINK & REFLECTDraw a picture of an atom.

• What do you remember from last year?

• What are the parts of an atom?• These parts are called subatomic

particles. Can you tell me anything about them?

Parts of the Atom

Subatomic Particle

Location Charge Mass (AMU)

Proton nucleus + 1 amu

Neutron nucleus No charge 1 amu

Electron Electron cloud

- 0.000548579909

Atomic Structure

• The Nucleus – a small region in the center of the atom composed, usually, of protons and neutrons.– Has a positive charge–Makes up most of the atom’s mass– Protons = 1 amu (atomic mass unit)

The Electron Cloud

• Electrons of an atom move in a certain region of space called the electron cloud.

• Since opposite charges attract, the negatively charged electrons stay around the positively charged nucleus

Atomic Number and Atomic Mass

Class Work & Homework

• Atomic Basics Worksheet