Chapter One
What is mass?
It is the measure of the amount of matter in an object.
What is matter?
Matter is objects that take up space and have mass.
How are matter and mass related?
Mass tells the amount of matter an object has.
Why do droplets of water stick together?
The water molecules are attracted to one another.
When liquid is heated how do the molecules move? When liquid is cooled how
do the molecules move?
Adding heat energy increases the motion of the molecules. Taking away heat energy decreases the
motion of the molecules.
How do particles behave in different states of matter?
In a solid, particles are cannot move past one another (they vibrate in place). It keeps a fixed shape.
There is the least amount of free space between particles.
In a liquid, particles can move past one another (they flow easily). It takes the shape of the container it
occupies. There is little free space between particles.
In a gas, particles move freely at high speeds. It takes the shape of the container it occupies. There is lots
of free space between particles.
How does energy affect the speed in which particles move?
The motion of the particles increases when the temperature increases.
The motion of the particles decreases when the temperature increases.
What does not have mass?
Energy does not have mass.
Chapter Two
How is energy transferred in the process of conduction?
It is when heat is transferred from one object to another or from one molecule to another. As one
molecule is heated it begins to move and shake rapidly. As it does so, it passes some of its heat energy
to other molecules around it. Through this process, all the molecules of an object pass heat from
another until they are all hot.
What does a water molecule consist of?
It consists of one oxygen atom and two hydrogen atoms.
What happens to the water molecule when it evaporates?
The heating of water causes the water molecules to move faster and faster until they break free from
the bonds that hold them in place as a liquid. The water molecule becomes a gas.
How does heat energy affect rates of evaporation?
The more heat energy there is the greater the rate of evaporation.
How does the process of evaporation work?
Molecules are in a liquid state. Heat energy causes the molecules to move faster and faster. This
movement weakens the attraction between the water molecules. The bonds break between the
water molecules to become a gas.
How does the process of condensation work?
COLD GLASS EXAMPLE-As the air near the glass cools, the molecules in the gas slow down. Because the
molecules slow down, they are able to attract to one another. This attraction allows the gas molecules
to turn to water molecules.
How does the process of freezing work?
Freezing occurs when the molecules of a liquid slow down enough that their attractions cause them to
arrange themselves into fixed positions as a solid.
How does the process of melting work?
Melting occurs when the molecules of a solid speed up enough that the motion overcomes the
attractions so that the molecules can move past each other as a liquid.
Chapter Three
What is the definition of density?
A measure of how much matter is in a certain space (volume).
What is the mathematical formula for density?
Does the sample size of a sample affect density?
The density of a substance remains constant, no matter the size of the substance.
What are two ways to find the volume of an object?
For a regularly shaped object, measure L*W*H. For an irregularly shaped object, you can use the
concept of water displacement.
How is density affected if two objects have the same mass but different
volumes?
The density would not be the same for two objects with the same mass, but different volumes.
How is density affected if two objects have the same volume but different
masses?
The density would not be the same for two objects with the same volume, but different masses.
How could you find out if an object sinks in water if you were only able to
calculate its density?
The density of water is about 1 gram per cubic centimeter. An object sinks if its density is greater than
that of the water.
Chapter Four
What are the components of an atom?
Do electrons have mass?
They don’t have much mass when compared to a proton and a neutron.
Define atomic mass:
Protons + Neutrons = atomic mass
Define atomic number:
The number of protons in an atom is the atomic number.
Define isotope:
An isotope is a form of an element that contains equal number of protons, but differing number of
neutrons.
Define ion:
An ion is an element that has lost or gained an electron.
Define element:
An element is substance that is made up of atoms of only one kind. They can’t be broken down into
simpler substances.
What happens to an element with an opposite charge?
Elements with opposite charges attract to one another.
What are energy levels?
It’s the area where electrons are found. These are areas are sometimes called shells. Shells surround the
center of the atom. The first shell holds two electrons. The second and third shells hold eight electrons.
The shell closest to the nucleus needs to be filled first.
What is the outermost energy level referred to? Why is it important?
It is referred to the valence level. It is important because these electrons are used for bonding.
What do the elements in a column share?
These elements have the same number of electrons in their valence level.
What do the periods tell you about the electrons energy levels?
These elements have the same number of shells.
What is covalent bonding?
The atoms are unstable because their out rings of electrons aren’t filled up. By sharing electrons with
other atoms, these atoms can fill up their outer rings and become stable.
What is ionic bonding?
It occurs when different elements trade electrons such that both elements now have a full outer shell.
If an element loses an electron, it becomes a positive ion. If an element gains and electron, it becomes a
negative ion.
What does a Lewis Dot Diagram look like?
Chapter Five
Define physical change:
Physical changes are about energy and states of matter. Sometimes substances change but keep the
same identity.
Define chemical change:
Chemical changes happen on a molecular level when you have two or molecules interact and create a
new molecule or two. Sometimes substances change to form new substances.
PHYSICAL VS CHEMICAL CHANGE:
Many changes of state are easy to characterize based on the definitions above, including the
following:
Physical Changes
Chemical Changes
Aluminum foil is cut in half.
Milk goes sour.
Clay is molded into a new shape.
Jewelry tarnishes.
Butter melts on warm toast.
Bread becomes toast.
Water evaporates from the surface of the ocean.
Rust forms on a nail left outside.
A juice box in the freezer freezes.
Gasoline is ignited.
Rubbing alcohol evaporates on your hand.
Hydrogen peroxide bubbles in a cut.
Food scraps are turned into compost in a
compost pile.
A match is lit.
You take an antacid to settle your stomach.
Your body digests food.
You fry an egg.
Define conservation of mass:
It implies that energy neither can be created nor destroyed, but can change from one form to another.
How do you balance an equation?
If you need help balancing equations, see Mrs. Schmidt for extra help.
What are reactants? What are products?
Reactants are present before the chemical change takes place.
Products are the substances formed during the chemical change.
A reaction arrow (yields) separates the reactants from the products.
How can mixtures be separated?
Some ways mixtures can be separated are through filtration, distillation, centrifuging.
What is an indicator and how is it used?
It is a substance that is used to identify a property of matter or identify the material itself.
What is kinetic energy?
It is energy in motion.
What is internal energy?
The energy associated with the disordered, random motion of molecules. It is the invisible energy on the
atomic scale.