Law of Conservation of Mass and Energy
States of Matter
Classification of Matter
Properties and Changes
Solutions
Atomic Structure
Periodic Table
Interaction of Matter
Chemical Equations
Acids and Bases
 

Solid:  has a definite shape and volume, the molecules are very close together and vibrate very slowly in place.
Liquid:  has a definite volume, but no definite shape.  Liquids take the shape of their container.  Molecules are further apart and move slowly.
Gas:  has no definite volume and no definite shape.  Molecules will move as far apart from each other as possible and move very fast.
Plasma: an electrically charged gas.  Molecules move faster than a gas.  The sun is made of plasma.  Plasma can not usually be contained on earth with our current technology.

Kinetic Theory of Matter:  When you add heat energy, molecules move faster and further apart.  When you remove heat energy, molecules move slower and closer together.  This is what causes matter to change from one state to another.  For example,  when you add heat energy to ice, the molecules move faster and further apart turning it into a liquid.

Evaporation:  When a substance changes from a liquid to a gas.
Condensation:  When a substance changes from a gas to a liquid.
Sublimation:  When a substance changes from a solid to a gas, skipping the liquid phase (dry ice).
Boiling Point:  The temperature at which a substance turns from a liquid to a gas.
Freezing Point:  The temperature at which a substance turns from a liquid to a solid.
Melting Point:  The temperature at which a substance turns from a solid to a liquid.

Elements:  Pure substances made up of only one type of atom.  All matter is made of atoms.  The types of atoms or matter are listed on the periodic table of elements.  Elements are represented by chemical symbols. Some examples are Cu for copper and H for hydrogen.  Elements are pure substances and thus, are always a solid color.  Mercury and Bromine are the only 2 elements that are a liquid at room temperature, the others are solids and gases.

Compounds:  Pure substances made up of two ore more elements combined chemically.  Compounds are represented by chemical formulas such as H2O for water and CO2 for carbon dioxide.  Compounds that contain carbon are called organic compounds and compounds that do not contain carbon are called inorganic compounds.  Compounds are pure substances and are thus, always one solid color.

Mixtures: Mixtures are not pure.  They are made up of two or more substances combined physically, but are not chemically.  Mixtures can easily be separated while pure substances can not. Some ways that mixtures can be separated is by  sifting, using a magnet, evaporation, solubility, filtration, chromatography and distillation.  Mixtures may or may not have the same composition throughout.  Mixtures may be more than one color or a solid color.   Any substance that is multicolored is a mixture.

Homogeneous mixture:  has the same composition through out
    Ex: fresh milk, mayonnaise
Heterogeneous mixture:  does not have the same composition through out
    Ex: Unstirred chocolate milk, unshaken italian dressing

Changes in Matter:  Some changes occur spontaneously while others require an outside force such as heat or light.  These changes may be classified as either a physical change or a chemical change.
Physical change:  a change in the size, shape, or state of matter of the substance.  No change occurs in the chemical composition of the substance.  For example:  tearing up paper, rolling tinfoil into a ball, breaking an egg, melting ice.
Chemical change:  a process that changes the chemical composition of a substance.  When a chemical change takes place, a chemical reaction between two or more substances occurs.  A chemical reaction is a reaction in which a new substance or substances are formed.  These new substances have different physical and chemical properties than the original substances.  For example, oxygen can combine with hydrogen to form water.  Water  (H2O) is very different from both the oxygen and hydrogen.   Evidence of a chemical change includes a new odor, a new color, fizzing, bubbling, heat or light given off, formation of a precipitate (a solid formed from two clear liquids).

-To help tell the difference between a chemical property and a chemical change:  a chemical property is in the future tense (it can happen), a chemical change is in the present or past tense (it is happening or it happened)

Solute: The ingredient in the solution of the lesser quantity.
Solvent:   The ingredient in the solution of the greater quantity.

Stirring, raising the temperature and crushing solids into smaller pieces all increase the rate of dissolving for a solution.

A solubility graph shows the rate that a solute dissolves in a solvent.

Ionic Solution:  A solution with ions (atoms with a positive or negative charge) in it.  Ionic solutions conduct electricity.  The more concentrated the solution, the better the solution will conduct the electricity.

Salt is made of ions (Na+ and Cl-);  therefore, seawater is an ionic solution.  Electricity from lightning will travel easily though ocean water.  Distilled water has no ions in it.  If lightning strikes a pool of distilled water, the electricity will not travel through it.  Electricity will travel more rapidly through the ocean compared to a lake because the ocean has a higher concentration of ions in it.

Atoms are the smallest unit of an element.

Atoms are made of three subatomic particles: protons, neutrons, and electrons.  The protons and neutron are located in the nucleus in the center of the atom.   The electrons move around the atom in orbits similar to the planets going around the sun.  This is also called an electron cloud.
 

Particle Type	Charge	Location in the atom	Mass
Proton	(+) positive	Nucleus	1  a.m.u.
Neutron	(0) neutral	Nucleus	1  a.m.u.
Electron	(-) negative	Electron Cloud	0  a.m.u.

This model of an atom is called a Bohr diagram

Maximum Number of Electrons per Energy Level

1st energy level	2 electrons
2nd energy level	8 electrons
3rd energy level	18 electrons
4th energy level	32 electrons

Atomic Number:  Every type of atom has a unique number of protons in it.  The number of protons in an atom is called the atomic number.  Oxygen has an atomic number of 8 and thus, any atom with 8 protons is an oxygen atom.  Carbon has an atomic number of 6, thus any atom with 6 protons is a carbon atom.  Atoms are arranged on the periodic table in order of atomic numbers.

Mass Number:  The mass number for an atom is equal to the number of protons plus the number of neutrons.  Every proton and every neutron has an atomic mass of 1 a.m.u. (atomic mass units).  Electrons have no mass.  The average oxygen atom has 6 protons and 6 neutrons, 6+6=12, thus, oxygen has an atomic mass of 12 a.m.u.  The average mass number for each atom is written on the periodic table of elements.  To calculate the number of neutrons in an atom you use the formula:

Mass Number  -  Atomic Number = Number of Neutrons

Ions:  Atoms with a positive or negative charge due to gaining or losing electrons.

If the number of protons does not equal the number of electrons, it is not an atom.  It is an ion.
Electrons rub off easily.  Metals tend to lose electrons and nonmetals tend to gain electrons. Electrons laying around at rest is what causes static electricity.
The charge of an ion = (number of protons) - (number of electrons)

Chemical symbols represent each element.  A chemical symbol can be a Capital letter such as K for potassium or a capital and a lower case letter such as Ca for calcium.

Periods:  the seven horizontal rows on the periodic table.  Elements on the first period have only one energy level, on the second period they have two energy levels and so on.
Groups:  Groups are also called families.  They are represented by the vertical columns on the periodic table.  Elements in the same group or family will exhibit similar chemical and physical properties.  Elements in the same group usually have the same number of electrons in the outer most energy level or some other similar arrangement of electrons.  Groups are numbered 1 - 18.

The atomic number and mass number is written in the box for each element.  The atomic number is the smaller quantity and the mass number is the larger quantity

Know some characteristics and where the following is located on the periodic table:
Metals:  Located to the left of the zig zag line, but not including hydrogen, they tend to lose electrons, conduct heat and electricity easily, and are malleable.
Nonmetals:  They are located on the right of the zig zag line, but they do not include Hydrogen. Nonmetals tend to gain electrons, do not conduct heat or electricity easily, are brittle, and a dull color.
Hydrogen:  Hydrogen is set apart from other elements because its properties do not fit any single group.  Sometimes it acts as a metal and sometimes it acts as a nonmetal.  Hydrogen  reacts easily with other elements.
Metalloids:  These have some characteristics of metals and some characteristics of nonmetals.  These are the elements that touch the zig zag line on the periodic table.
Transition Elements:  Groups 3 -12 in the middle of the periodic table, most are hard and shiny, have high melting points, are good conductors, and are less reactive than the other metals,
Alkali Metals:  Group 1, not including hydrogen, are very reactive.  They have one electron in their outer most energy level, found only in nature as positively charged ions since the outer most electron is easily lost, they combine with negatively charged ions to form salts, soft, low densities, melt at low temperatures.
Alkaline Earth Metals:  Group number 2, have 2 electrons in outer most energy level, occur in nature as ions , reactive, but not as reactive as alkali metals.
Rare Earth Elements:  These are elements that are rarely found on earth or are created synthetically in a lab.  They are located on the bottom of the periodic table, sometimes called rare earth metals.
Noble Gases:  They are the group on the far right side of the periodic table in family number 18.  These gases are very stable and do not usually react with other chemicals and are not combustible.  They are stable because they have their outer most energy level filled.  All the other elements want to be like a noble gas and have their outer most energy level filled.
Halogens:  Group number 17, means "salt-former", combines with metals to form salts.
Radioactive Elements:  Different tables have different symbols or ways of identifying these elements.  The nuclei of radioactive elements are unstable and break down easily.

For each chemical formula count the number of elements, the number of atoms for each element, and the total number of atoms in the molecule.
 

Chemical formula	Number of elements	Number of atoms for each element	Total number of atoms in each molecule
H2O	2	H=2 O=1	3
NaNO3	3	Na=1 N=1 O=3	5
ZnCl2	2	Zn=1 Cl=2	3

Ionic Compounds:  Compounds that contain ions, held together by ionic bonds.  This is also called a binary compound.  It is easy to write a formula for a binary compound when given the oxidation numbers of two ions.  The oxidation number is the charge of the ion.  The following method is informally known as a criss-cross.  The oxidation numbers will become the subscript numbers for the opposite elements.

Magnesium has an oxidation number of 2+ and chlorine has an oxidation number of 1-.
Mg₂+  and Cl₁- combine (and criss cross)  (Mg₂+Cl₁- ) to form MgCl₂
Remember, the subscript number is not written if it is equal to one, and was only used here to help explain.

4H + 2O  2H₂O

Terms to know for chemical reactions:

Reactants:  The chemicals you start with at the beginning of the reaction.  In the above example the reactants are 4H + 2O.
Products:  The chemicals you have at the end of the reaction.  In the above equation, the products are 2H₂0.
Subscripts:  Describe the number of atoms for each element in the molecule.  In 2H₂O, the small 2 is the subscript.  If there is not subscript, there is only one atom.
Coefficient:  Describes how many molecules you have.  In the example reaction, the following  in bold were coefficients 4H + 2O2H₂0.  We have 4 hydrogen and 2 Oxygen atoms in the reactants.  We have 2 molecules of H₂O in the products. To count the number of atoms, multiply the coefficient by the subscript.  If there is no subscript, the subscript is equal to one. Two molecules of water or 2H₂O are made of 4 hydrogen (2x2=4) and 2 oxygen (2x1=2) atoms.

The Law of Conservation of Mass states that in a chemical reaction matter can neither be created or destroyed.  Therefore, in a chemical reaction, the number of atoms of each element must be equal on both sides of the equation and the mass of the reactants must equal the mass of the products.
 
4H + 2O2H₂0
 

Number of each type of atom for the reactants	H=4 O=2
Number of each type of atom for the products	H=4 O=2
Atomic mass of the reactants	36 a.m.u.        (4*1=4    16*2=32     32+4=36)
Atomic mass of the products	36 a.m.u.        (4*1=4    16*2=32     32+4=36)

A chemical equation must be balanced.  This means that both sides of the equation must have an equal number of atoms for each element.  When you balance an equation, you can only change the coefficients and you can not change any other part of the equation.

There are 4 main types of chemical reactions:

Synthesis or Composition Reaction:  two or more substances combine together to form  one  larger substance.

Na + ClNaCl

Decomposition Reaction:  One substance breaks down or decomposes into two or more smaller substances

NaClNa + Cl

Single Displacement Reaction:  One  element or set of elements replaces another element or set of elements in a compound.

Zn +Cu(NO₃)₂Zn(NO₃)₂ + Cu

Double Displacement Reaction:  Elements or sets of elements trade partners with elements  or sets of elements in another compound.

AgNO₃ +NaClAgCl  + NaNO₃

An indicator is a substance that will produce a predictable change in color when it comes in contact with an acid or a base.

Litmus paper is one example of an indicator.  Litmus paper turns blue when in contact with a base and turns pink when in contact with an acid.

You can change the pH of a solution by adding acid (H+) or base (OH-). For example;  if you have a swimming pool and you test the water and discover the pool is too acidic (too many H+ ions), you add base to the pool water (OH-).

If the .......

H+ ions = the OH- ions in the solution, it is neutral.
H+ ions > the OH- ions in the solution, it is an acid or acidic
H+ ions < the OH- ions in the solution, it is a base or alkaline.

NaOH + HClNaCl + H2O
 

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