1. MATTER
Chapter 8 Lesson 1

2. What is matter made of?
MATTER- anything that has mass and takes up space
Matter is all around you! You are matter and so it this book and the air you breathe
Matter is made of building blocks called chemical elements
ELEMENT- material that cannot be broken down into anything simpler
Scientists know of more than 112 elements which are classified as metals, nonmetals, or metalloids.
Metals are shiny, conduct heat and electricity, and bend easily
Nonmetals are elements that are dull, poor conductors of heat and electricity, and brittle
Metalloids have some properties of metals and some of nonmetals

3. What is matter made of? INSIDE ATOMS
In 1803, John Dalton proposed that elements are made of tiny particles called atoms
ATOM- the smallest unit of an element that still retains the properties of that element
Atoms are made of even smaller particles
Proton- particle with one unit of positive electric charge
Electrons- smaller particles with one unit of negative electric charge. They move within the space outside the nucleus
Neutrons- particle with no electric charge- it is neutral
Atomic Number- number of protons in an atom
Atomic Mass Unit (amu)- Protons and neutrons have about the same mass.
In 1913, Niels Bohr pictured an atom’s electrons moving around the nucleus like planets moving around a star

4. What are compounds? COMPOUND- forms when two or more elements combine
You’ve probably used table salt before which is made from two elements: sodium and chlorine.
Compounds have properties different from their individual elements. The joining of the atoms is what gives the sodium chloride new and different properties
All compounds have chemical names, and many have common names as well
The chemical name indicates which elements make up the compound: rust = iron oxide.

5. Molecules Some compounds, such as water, are made of molecules
Forms when two or more atoms join together and share electrons
Water Molecule = H2O (2 Hydrogen + 1 Oxygen)

6. How are elements grouped?

7. What forms can matter have?
A state of matter is one of the three common forms that matter can take: solid, liquid, or gas
You interact with these states every day and each state has its own properties
Solids stay in a definite shape with a definite volume no matter what container it is in
A rock is a solid.
Liquids move more freely than a solid. They can take shape of its container
Water is a liquid
Gas particles have no definite shape or volume. At room temperature, gas moves around to fill their container. It can expand and fill things such as tires or balloons

8. Changes in states of matter
Elements can change states of matter
Water is a liquid. When frozen it can change to a solid in the form of ice. When it is heated (boiled) it turns into gas (steam).

9. Which term defines any substance that cannot be broken down into a simpler substance?
Atom
Compound
Element
Molecule
Answer: C-Element
Let’s take a look…
Turn and talk with a partner before you answer

10. A few more…
When 2 oxygen atoms bond chemically with 2 hydrogen atoms, hydrogen peroxide is formed.
Which phrase defines this substance?
An element
A molecule
A compound
A mixture
Answer: C-Compounds are formed when atoms are chemically bonded together
As water evaporates, which best explains the change that is occurring?
A gas changes to a liquid
A gas changes to a solid
A liquid changes to a gas
A liquid changes to a solid
Answer: C- as water is heated, it begins to evaporate and is in gas form (usually as steam).