General Chemistry 2008

 The science of matter and the reactions caused when different kinds of matter interact. What people use chemistry to do their jobs?

 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.

What happens to carbon dioxide (CO 2 ) when it mixes with water (H 2 O)? CO 2 + H 2 O Carbon dioxide + water

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!

 The smallest unit of matter How small is small? 1 Atom of Helium Diameter = 50 picometers Mass = 1.67 x kilograms This is a carbon atom. Atoms most common in living organisms: carbon nitrogen hydrogen oxygen

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 (-) 1 st Cloud: 2 electrons 2 nd Cloud: 8 electrons 3 rd Cloud: 8 electrons

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: ___________________

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

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

1. Draw the Nucleus 2. Add protons (+) and neutrons (o) into the nucleus 3. Draw at least one electron level. 4. Add electrons remembering the number each level can hold; you may need to add more electron levels 1 st : 2 electrons 2 nd : 8 electrons 3 rd : 8 electrons

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

 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)

COVALENT BOND: SHARING OF ELECTRONS IONIC BOND: GIVING AND TAKING OF ELECTRIONS Why do atoms bond (stick to) other atoms? Stable Atoms: