8th Grade 11/15 Do Now:

1
8th Grade11/15 Do Now

• Define ion.
• What are examples of elements that could be ions?

2
What do halogens and alkali metals create?

• Halogens form salts.
• NaCl is an example of a chemical bond
• Chemical bond is the force that holds two atoms
  together

3
How elements bond

• Atoms form bonds with other atoms using the
  electrons in their outer energy levels
• Losing electrons
• Gaining electrons
• Pooling (sharing) electrons

4
Ion

• Atom that is no longer neutral. It has gained or
  lost an electron
• Na loses an electron and becomes positive Na
• Cl gains an electron and becomes negative Cl-

5
Ionic Bond

• A strong attraction which holds oppositely
  charged ions together
• Why would these ions have a strong attraction to
  one another?

6
Agenda

• Half the class will continue with the ionic bonds
  gizmo
• Website www.explorelearning.com
• Login olgcscience
• Password olgcscience
• Half of the class will read p. 472-474. Take
  notes on these pages. Begin Lab on p. 481.
• Work in pairs for the lab.
• 5 cm disks
• Define chemical formula.
• Write formulas and answers on theme paper.