1. Basic Chemistry CHAPTER 2-2

2. Inert Elements  Atoms are stable (inert) when the outermost shell is complete

3. Inert Elements  Atoms are stable (inert) when the outermost shell is complete  Atoms will gain, lose, or share electrons to complete their outermost orbitals and reach a stable state

4. Inert Elements  Atoms are stable (inert) when the outermost shell is complete  Atoms will gain, lose, or share electrons to complete their outermost orbitals and reach a stable state  Atoms are considered stable when their outermost orbital has 8 electrons (With exception to the first shell

5. Inert Elements

6. Reactive Elements  Valence shells are not full and are unstable  Tend to gain, lose, or share electrons  Allow for bond formation, which produces stable valence

7. Molecules and Compounds  Molecule: Two or more like atoms combined chemically  Compound: Two or more different atoms combined chemically

8. What are chemical reactions?  What do you remember?

9. What are chemical reactions?  Atoms are united by chemical bonds OR  Atoms dissociate from other atoms when chemical bonds are broken

10. Chemical Bonds  Ionic vs. Covalent  https://www.youtube.com/watch?v=fH GSSV466Gk

11. Ionic Bonds  Form when electrons are completely transferred from one atom to another  Ions  Charged particles  Anions - negative  Cations - positive  Either donate or accept electrons

12. Ionic Bonds +– Sodium atom (Na) (11p + ; 12n 0 ; 11e – ) Chlorine atom (Cl) (17p + ; 18n 0 ; 17e – ) Sodium ion (Na + )Chloride ion (Cl – ) Sodium chloride (NaCl) ClNaCl Na

13. Covalent Bonds  Atoms become stable through shared electrons  Single covalent bonds share one pair of electrons  Double covalent bonds share two pairs of electrons

14. Covalent Bonds - Example

17. Polarity  Covalently bonded molecules

18. Polarity  Some are non-polar  Electrically neutral as a molecule  Some are polar  Have a positive and negative side

19. Polarity  https://phet.colorado.edu/en/simulation/mol ecule-polarity

20. Hydrogen bonds  Weak chemical bonds  Hydrogen is attracted to the negative portion of polar molecule  Provides attraction between molecules

21. Hydrogen bonds

22. Adhesion and Cohesion