Chemical Bonding

1. Chemical Bonding Chapter 13

2. Electrons and Chemical Bonding • Have you ever stopped to consider that by using the 26 letters of the alphabet, you make all of the words you use every day? Although the number of letters is limited, you combine them in different ways to make a huge number of words. This is the same with elements. We combine them to make different substances.

3. Combining Atoms Through Chemical Bonding • - is the joining of atoms to form new substances • The ___________ of these new substances are ____________ than the _________ of the original substance. • When chemical bonds form, __________ are ________, ________, or _________.

4. Electron Number and Organization • To understand how atoms form chemical bonds, you need to understand how ________________ are arranged in an atom. • The number of electrons in an atom = ___________________. • The number of protons can be determined by the _____________. • The electrons are organized in __________________. • 1st Energy Level: Diagram Fluorine: • 2nd Energy Level: • 3rd Energy Level:

5. Outer-Level Electrons and Bonding • Not all __________ in an atom take part in a bonding. • Most bonds form using the outer most electrons called _________________. • - an electron in the outermost energy level of an atom.

6. To bond or Not to Bond • Not all atoms bond the same way. • The number of _____________determines if an atom will form a bond. • Atoms want to be like ___________ (have a full outer shell of electrons). • __ valence electrons • __ valence electrons like He • Atoms bond by ________, ________, or _________ electrons to have a ________ outer most energy level like the noble gases.

7. Ionic Bonds • -are formed when __________ are _________ from one atom to another. • Ionic bonds form so that the outermost energy levels of the atoms in the bonds are ____________. • Ionic bonds form between a ________ and a ______________ Sodium Chlorine

8. Ionic Bonds • Charged Particles (Magnets) • A transfer of electrons between atoms changes the number of _________ in each atom but the number of ________ stay the _______. • The negative charges and positive charges no longer __________ and the atom becomes an _______. • _________- an atom that gained or lost electrons

9. Ionic Bonds • Charged Particles Continued • An atom cannot ________ electrons without a nearby atom _________ electrons and visa versa. • Metals – tend to ______ electrons and become a ________ ion (_________) • Nonmetals – tend to ______ electrons and become a ______ ion (________) • _______ - the ending that is given to atoms that gain electrons • Oxygen = __________ • Fluorine = __________ • Sulfur = __________

10. Ionic Compounds • Metals tend to ______ a certain number of ________ depending on their number of __________ and become _______ charged • Nonmetals tend to ______ a certain number of ________ depending on their number of __________ and become _______ charged

11. Ionic Compounds • When ionic bonds form, the number of ______________ _____ by the metal ________ the number of electrons ___________ by the nonmetal atoms. • The ions that bond are _______ but the compound formed are _________ because the charges on the ions ______________.

12. Ionic Compounds • Writing Ionic Compounds ( _______ + __________) • Write the metal with its’ charge • Write the nonmetal with its’ charge • Criss- Cross the charges • Only bring down the #, NOT the charge • Examples: • Sodium and Chlorine • Barium and Chlorine • Potassium and Oxygen • Litium and Sulfer

13. Ionic Compounds • Naming Ionic Compounds • Name of Metal + nonmetal w/ ending –ide • Examples: • Sodium and Chlorine • Barium and Fluorine • Potassium and Oxygen • Lithium and Sulfur

14. Ionic Compounds • When ions bond, they form a repeating 3-dimensional pattern called a _______________.

15. Covalent Compounds • Covalent Bonds are formed when two ________________ _________ electrons. • _____________ – a bond that forms when atoms share one or more pairs of electrons

16. Covalent Compounds • Examples of covalent compounds: 1. 2. 3. • Properties 1.____ melting points 2. ____ boiling points 3. Brittle as a solid • Substances containing covalent bonds consist of individual particles called _________________. • ______________ - a neutral group of atoms that are joined together by one or more covalent bonds.

17. Covalent Compounds • Simple Covalent Compounds • When found in nature as pure elements, these seven elements exist only as two atoms covalently bonded. • H2 • O2 • N2 • Cl2 • Br2 • I2 • F2

18. Covalent Compounds • How to draw covalent molecules: using electron dot diagrams • Write the symbol of the element and place one dot around the symbol for every valence electron in the atom. • Examples: Carbon Oxygen Krypton Hydrogen

19. Covalent Compounds 2. Combine the elements where they can share electrons so each have a full outer shell. (The shared electrons are the covalent bond) • Examples: • Hydrogen + Chlorine • Fluorine + Fluorine • Water • Oxygen + Oxygen

20. Naming Covalent Compounds Prefixes One = _____ Two = _____ Three = _____ Four = _____ Five = _____ Six = _____ Seven = _____ Eight= _____ Nine = _____ Ten = _____ Rules: Prefix + namePrefix + name –ide Rule: Do NOT use mono- on the first element Examples: CO CO2 C2H4 P2O5 N3P6 Covalent Compounds

21. Metallic Bonds • Properties of Metals 1. 2. 3. • Metals are malleable and ductile because of the presence of a ___________________________________. • Metallic Bond –

22. Metallic Bonds • The _______ ions in a metal form a lattice that is held in place by strong ______________ between the _________ ions and the surrounding _________. • Swimming in electrons.