1. Comparing Kinds of Matter
Chapter 9
Comparing Kinds of Matter

2. Lesson 1 Properties of Matter
Mass-the amount of matter in an object; measured on a pan balance; measured in kilograms or grams.
Weight-how strongly gravity pulls on an object; measured in pounds.
Volume-measures how much space matter takes up; a marble’s volume makes the water level rise when you place it in a graduated cylinder.

3. Matter-anything that has mass and volume
Lesson 1 continued…
Matter-anything that has mass and volume
Density-the amount of mass for each mL (or cm³) of a substance; as you add more marbles to a large box, you are increasing the box’s density
Density=mass/volume
If a material is dense, matter is packed closely together.

4. Buoyancy- the resistance to sinking
Lesson 1 continued…
Buoyancy- the resistance to sinking
Depends on density
If you change the mass or volume of an object, you can change whether or not it will float
If you have a toy boat and keep adding mass to it, it will sink
Think of a buoy in the water!

5. 3 important properties of elements
Lesson 2 Elements
Element-a material that cannot be broken down into anything simpler by chemical reactions.
3 important properties of elements
State of matter at room temperature
The way they combine with other elements
Whether they are metals, nonmetals, or metalloids
Most elements are solid at room temperature
Metals-elements that share common properties like shiny luster, conductivity, and flexibility
Wood is not a good conductor of electricity, but copper is!
See the shiny luster!

6. Lesson 2 continued Look at the variety of colors!
Each color represents solids,
liquids, or gases (metals,
non-metals, or metalloids). To
See an up close version p. 494
in your textbook has a great example!

7. Lesson 2 continued…
Atom- the smallest unit of an element that keeps the properties of that element.
Nucleus-the hard core/center of an atom; made up of protons and neutrons.

8. Neutron- a particle with no electric charge; it is neutral
Lesson 2 continued…
Proton- a particle with one unit positive charge; the number of protons in an atom is called the atomic number and determines which element it is.
Neutron- a particle with no electric charge; it is neutral
Electron- smaller particle with one unit of negative electric charge each; electrons move around in the space outside the nucleus.

9. Molecule- particle with more than one atom joined together.
Lesson 2 continued…
Molecule- particle with more than one atom joined together.
Elements are grouped together by their properties in the periodic table
On Earth, the most common elements by far are hydrogen and helium
Helium

10. Lesson 3 Metals, Nonmetals, and Metalloids
Malleability- the ability to be bent, flattened, or hammered without breaking
Ductility- the ability to be pulled into thin wires without breaking.
Gold is both malleable and ductile.
Copper is often drawn into wires for conducting
electricity.

11. Corrosion-when metals combine with nonmetals from the environment.
Lesson 3 continued…
Corrosion-when metals combine with nonmetals from the environment.
Iron “corrodes” by rusting, which causes the corroded iron to flake away.

12. One of the most resourceful metals we use today is aluminum:
Lesson 3 continued…
One of the most resourceful metals we use today is aluminum:
Often used in mirrors because it is inexpensive and can be polished to be reflective.
Aluminum foil wrapped around food will trap heat inside by reflecting it.
Can be used to conduct energy cheaply; it is used in electrical wiring, water heaters, and radiators.
Easily coated with a thin layer of oxygen to help prevent corrosion.