1. Atoms and the Periodic Table

2. Definition: Element and Atom
All matter is made of one or more elements.
The atom is the smallest particle of an element.

3. Atomic Structure Central nucleus surrounded by one or more electrons.
The three subatomic particles are called protons, electrons, and neutrons.
Different atoms have different #s of subatomic part.

4. Proton p+ Protons have a + electric charge.
p+ have a mass of 1 atomic mass unit (amu).
p+ are found in the center core of the atom called the nucleus.

5. Neutron n0 Neutrons are electrically neutral. No charge.
n0 have a mass of 1 amu.
n0 are also located in the nucleus.

6. Electron e- The electron has a - electric charge.
The e- has a mass of amu. (The mass of the e- is so small compared to the p+ and n0 that it is ignored.)
The e- is found moving around the outside of the nucleus. (e- cloud)

7. Structure / Parts of the Helium Atom
Electron
Neutron
Proton

8. Electron Placement
e- are placed in shells (energy levels, orbitals) which are located at different distributions from the nucleus
The shell closest to the nuclei is the 1st shell and can hold a max of 2 e-.
Shell no. 2 can hold a max of 8 e-.
Valance shells (outermost) can hold a max of 8 e-.

9. Periodic Table
The periodic table gives the following information about each element and it’s atoms.
Atomic Number
Mass Number
(Atomic Mass)
Element (Chemical)
Symbol

10. Using the Periodic Table
Chemical symbol - an abbreviation for each element. It’s either 1 or 2 letters w/ the 1st letter being capital
atomic # - the smaller of the 2 #s. This one # reveals 2 pieces of info. It tells the # of p+ and e-.

11. The atomic mass # (or mass #) tells the sum of the # of p+ and n0.
This # is used to find the # of n0
# of n0 = mass # (rounded) – atomic #

12. Element
Protons and Electrons
Neutron
Carbon
Oxygen

13. Atom Name
Protons
Neutrons
Carbon 12 6
Carbon 14 8

14. Parts of the Periodic Table
___________ called groups or families.
Elements in each group, have _____ properties and characteristics.
Elements in horizontal rows called _____.

15. Sample Periodic Table

16. Regions of the Periodic Table
The periodic table is divided into three different regions. The three regions are the metals, metalloids, and the non – metals which include the noble gases.

17. Metals
Physical properties: hardness, shininess, malleability, and ductility.
Malleable material can be pounded into shapes.
Ductile material can be pulled out or drawn into a long wire.
Metals are good conductors of heat and electricity. Most are also magnetic as well.

18. Nonmetals
Noble gases (inert gases) located in family 18. They are stable and are not reactive with other elements. Other elements want to be like them and have their outer shell full.

19. Metalloids Elements that form the zigzag line in the periodic table.
The metalloids have some properties of a metal and some properties of a nonmetal.
For example, these elements have varying abilities to conduct electricity.

20. Alkali Metals

21. Alkaline Earth Metals

23. www.chemicalelements.com www.chem4kids.com www.webelements.com
Additional Resources