Matter, Atomic Structure-Periodic Table ISCI 2002 Spring 2009

Matter Anything that has mass and occupies space Matter – all substances Properties of matter 1. macroscopic 2. microscopic

Classification of Matter Heterogeneous Matter mixture Peanut butter Pure substance Ice floating in water Homogeneous Matter gasoline Pure substances Sugar

Atomic Structure 1. Size and general structure 2. Parts - Atom Small; cannot be seen with visible light 2. Parts - Atom Nucleus Protons and neutrons Energy levels / electron clouds Electrons 3. Atoms are mostly empty space Nucleus determines the mass of the atom

Subatomic Particles Atomic mass unit (amu) – hydrogen atom (1 amu) Electron mass = 1/2000 amu

Nucleus of the Atom 1. Proton + Neutron 2. Electrons Mass of the atom 1/2000 of one amu Not included in the mass

Atomic Number Atomic Number – Periodic Table Number of protons in an atom Protons = electrons Using your periodic table determine the number of protons and electrons in the following atoms Sodium Chlorine Nitrogen Lithium

Number of neutrons and protons Combined mass – Mass Number Atomic Weight Average of all the isotopes in an element. Carbon = 12.011 amu Combination of three carbon isotopes

Isotopes 1. Elements are composed of several different types of the same atom Same type of atoms with differing number of neutrons 2. Carbon 3 isotopes Carbon 12, 13, and 14 Calculating neutrons

Using the mass number and atomic number to determine the subatomic particles The atomic number equals the number of protons. Protons always equal the number of electrons!

Periodic Table 1. Symbol 2. Atomic Number Number of protons 3. Atomic Mass-(Average Atomic Mass) Mass of neutrons and protons 4. Group Vertical 5. Period Horizontal

Periodic Table

Periodic Table

Groups and Periods Alkaline Earth metals Noble Alkali Halogens Transition Metals

Drawing Planetary Models of Atoms Energy Level (Electron Shell) Orbitals Max Number of electrons Valence Electrons 1 S 2 S and P 8 3 S, P, D 18 4 S, P,D 32 5 S, P,D,F 50 Orbital Maximum Electrons S 2 P 6 D 10 F 14

Drawing Planetary Models 1. Look at the atomic number 2. Determine the total number of electrons 3. Draw each energy level with correct number of electrons Next – Dot Diagrams Draw only the ‘valence’ electrons S and P - orbitals only

Chemical and Physical Properties Appearance – hard or soft; dull or shiny; color Density; melting point and boiling point Chemical Properties- describes changes of composition the substance undergo’s during a chemical change What is required to bring about the change Temperature, heat, number of electrons, etc.

Chemical and Physical Properties Extensive Property Depends on the ‘quantity’ of matter in a sample Cannot be used to characterize a type of matter Volume, mass Intensive Property Property shared by all examples of a specific type of matter Density (m/v); color; melting point; solubility; acidic or alkaline The density of water is 1.0 g/cm3