COLEMAN BIOLOGYGeneral Chemistry 2008

Chemistry

The science of matter and the reactions caused when different kinds of matter interact.

What people use chemistry to do their jobs?

Matter

Anything that has mass and volume.

What are some examples of matter that can be found in this classroom?

Does matter exist if we can’t see it?

Give an example of something that is matter but we can’t see it.

Why do we need to know chemistry?

What happens to carbon dioxide (CO2) when it mixes with water (H2O)?

CO2 + H2O

Carbon dioxide + water

Carbonic Acid Pollution

These organisms and the organisms that eat them are relying on someone who knows about chemistry to

decrease the carbonic acid pollution.We need to know basic chemistry to better understand

how living organisms react to their environment!

Atom

The smallest unit of matter

electron

neutron

proton

How small is small?1 Atom of Helium

Diameter = 50 picometersMass = 1.67 x 10-27

kilograms

This is a carbon atom.

Atoms most common in living organisms:• carbon• nitrogen• hydrogen• oxygen

The Atoms Family

Subatomic Particles:The parts of the atom

NUCLEUS: CENTER OF THE ATOM

•PROTONS – POSITIVELY CHARGED PARTICLES (+)

•NEUTRONS – PARTICLES WITH NO CHARGE (0)

ELECTRON LEVELS (CLOUDS): INVISIBLE RINGS AROUND THE

NUCLEUS

•ELECTRIONS – NEGATIVELY CHARGED PARTICLES (-)

1st Cloud: 2 electrons2nd Cloud: 8 electrons3rd Cloud: 8 electrons

Particle Charges

Protons have a positive charge (+)Neutrons have no charge (0)Electrons have a negative charge (-)

For the following pairs, decide if the particles will attract or repel.

• proton and electron: ____________________• proton and neutron: ____________________• proton and proton: _____________________• electron and electron: ___________________• neutron and neutron: ___________________

Atomic Structure & The Periodic Table

electron

neutron

proton

ATOMIC NUMBER•The number of protons an atom has.•This number never changes!•Can be found on the periodic table

ATOMIC MASS•Mass of atom is found in the nucleus•Atomic Mass = Protons + Neutrons

DRAWING ATOMS

1. Draw the Nucleus2. Add protons (+) and neutrons (o) into the

nucleus3. Draw at least one electron level. 4. Add electrons remembering the number each

level can hold; you may need to add more electron levels

1st: 2 electrons2nd: 8 electrons3rd: 8 electrons

Periodic Table of ElementsA chart of all elements known to man. Arranged in rows and columns. In order of atomic number.

Periodic Table of Elements

Element – a substance made of only one kind of atom Example: Carbon Atoms can combine to make

elemental carbon in the form of coal or diamonds.

Atomic Number – number of protons and electrons; atomic number of an atom never changes

Atomic Mass – number of protons + neutrons (mass of atom is found in the nucleus)

Atomic Bonds

COVALENT BOND: SHARING OF ELECTRONS

IONIC BOND: GIVING AND TAKING OF ELECTRIONS

Why do atoms bond (stick to) other atoms?

Stable Atoms: