1. Announcements: We will meet in the computer lab, Room 301, tomorrow, the 17 th.

2. Academic Content Standards PHYSICAL SCIENCES o Benchmark A: Describe that matter is made of minute particles called atoms and atoms are comprised of even smaller components. Explain the structure and properties of atoms.

3. What is an atom? The smallest particles of matter are called atoms. Neutrons have no charge Protons have a positive charge Electrons have a negative charge

4. Atomic Charges If an atom loses an electron, it becomes positive. If an atom gains an electron, it becomes negative. Positive and negative charged atoms are called ions.

5. The Periodic Table of Elements All the different types of atoms are called elements and are organized onto the periodic table. Each element has a different number of protons/electrons. All atoms of the same type of element contain the same number of protons. This is called the atomic number. The atomic mass is shown at the bottom of the element; it is a combination of the weight of protons and neutrons in that element

7. The Periodic Table of Elements The same type of element will always have the same number of protons, but that element can differ in the number of neutrons. This is called an isotope; each isotope of an element has a different atomic mass Example: Carbon-12 Carbon-14

8. The Periodic Table of Elements Periodic Table is organized to relate similar properties together o Horizontal rows are called periods and indicate how many energy levels (shells) the elements have (e.g. Elements in period two have two energy shells to fill) o Vertical columns are called groups or families and show how many electrons are in the outermost energy shell o The table is usually color-coded to show what physical state the elements are in

10. Bohr Model of An Atom

11. References http://www.google.com/imgres?imgurl=http://www.vtai de.com/png/images/atom.jpg&imgrefurl=http://www.vt aide.com/png/atom.htm&h=444&w=443&sz=96&tbni d=7IfbyagU8DpuYM:&tbnh=127&tbnw=127&prev=/im ages%3Fq%3Datom&usg=__dO_Eep0bu4MAGXfRT 6kaLXvAulw=&ei=fnm2Sp66HqiI8Abt4IHEDQ&sa=X &oi=image_result&resnum=6&ct=image http://img.brothersoft.com/screenshots/softimage/p/p eriodic_table-196985-1228791898.jpeg http://img.brothersoft.com/screenshots/softimage/p/p eriodic_table-196985-1228791898.jpeg http://www.corrosionsource.com/handbook/periodic/p eriodic_table.gif http://www.corrosionsource.com/handbook/periodic/p eriodic_table.gif http://physics.gmu.edu/~rms/astro113/images/L3/l03 X44.GIF http://physics.gmu.edu/~rms/astro113/images/L3/l03 X44.GIF