CHEMISTRYThe smallest way to describe our Earth

Atoms

This is the smallest unit of an element having the same properties of that element

Arrangement and types of atoms give matter its properties

Atoms

Elements

Elements are a substance that can not be broken down into a simpler form

All the elements can be found on the periodic table.

There are 94 elements that are naturally occurring in nature. Hydrogen- plutonium. All the rest are man-made.

Elements

The elements after bismuth (element 83) the elements are not very stable and begin to decay

Periodic Table

Elements

A single atom of an element is made up of 3 basic parts: protons, neutrons, and electrons

Protons and Neutrons are concentrated in the middle of the atom

The electrons rotate around the atom

Atom

Elements

Protons are particles that have a postive electric charge

Neutrons are particles that have no electric charge (neutral)

Electrons are particles that have a negative electric charge

Mass and Atomic numbers The atomic mass is equal to the sum of

protons and neutrons in the nucleus of an atom

The atomic number is equal to the number of protons in the nucleus

Elements

In a neutral atom (an atom with a neutral charge) will have the same number of protons and electrons

In a neutral atom the number of neutrons can vary but unless specified differently will also be the same as protons.

Compounds

Compounds are substances that are made up of two or more elements chemically combined that cannot be separated physically

Compounds are held together by chemical bonds

Chemical Bonds

Chemical Bond- Foces that hold together the atoms that combine to make up a compound

Types of chemical bonds: Covalent bonds and ionic bonds

Types of Bonds

Ionic bonds are a combination of oppistely charged ions

Ions are electrically charged atoms Atoms become ions by losing or gaining

electrons If an atom gains electrons it is negatively

charged If an atom loses electrons it is positively

charged

Types of Bonds

Covalent bonds is the attraction of two atoms through a sharing of electrons.

Water is an example of a covalent bond

Mixing things up

Mixture is many different types of objects mixed together.

This is not a bond. These objects are just mixed together

Mixing things up

A type of mixture that deals with dissolving substances.

Ex. Salt water, coffee, Tea with sugar

Mixing things up

Heterogeneous mixture is a combination of materials that are easily recognizable.

Ex. Soil

Homogeneous mixtures are a combination of materials that are not easily recognizable.

Ex. Milk

Matter

As we have talked about before matter is anything that takes up space and has a mass

In other words, it has a volume and weighs something.

Matter

Matter has two different properties that you need to be able to distinguish between; physical and chemical properties

Physical Properties

Physical properties are those that you can observe without changing a substance into a new substance

Ex. Color, shape, odor, density

Chemical Properties

Chemical properties are those that descrbe how one substance changes when reacting with another substance

Ex. Rusting of Iron, burning of wood

4 States of Matter

There are four states of matter in which they can exist: solid, liquid, gas, and plasma

Each has its own way of forming the atoms of a certain substance

Solids

Solids are formed by atoms or molecules that are in a fixed position relative to each other

Atoms are molecules are strongly attracted to each other and resist being separated

Set Shape and set Volume

Types of Solids

Crystalline structures- have regular shapes and may cleave along well-defined surfaces

Glasses- They do not break along well defined surfaces. Shatter or break into lots of tiny pieces.

Liquids

Liquids is a type of matter where the atoms or molecules remain close to one another, but are fee to change positions with each other.

This allows liquid to flow as it takes the shape of its container

Set Volume but takes shape of container

Gases

Gases contain atoms or molecules that have very little attractive force on each other

Fill entire container no matter how large or small

NO set volume and No set shape

Plasma

This is matter heated to temperatures much higher than we normally see.

Plasmas are composed of ions and free electrons

You can find these in lightning bolts, florescent lights, and even stars