Chapter 9 Science notes

Chapter 9
Comparing Kinds of Matter
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.
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
If a material is dense, matter is packed closely together.
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!
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!
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!
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.
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.
Lesson 2 continued…
• Molecule- particle with more than one atom joined
• Elements are grouped together by their properties in the
periodic table
• On Earth, the most common elements by far are
hydrogen and helium
Lesson 3 Metals, Nonmetals, and
• Malleability- the ability to be bent, flattened, or
hammered without breaking
• Ductility- the ability to be pulled into thin wires without
Gold is both malleable and ductile.
Copper is often drawn into wires for conducting
Lesson 3 continued…
• Corrosion-when metals combine with nonmetals
from the environment.
Iron “corrodes” by
rusting, which causes the
corroded iron to flake
Lesson 3 continued…
• One of the most resourceful metals we use today is
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