Understanding Ions and Noble Gas Electron Configuration

1. More on Ions

2. Record into your notes Achieving Noble Gas Electron Configuration An ion forms when an atom • loses electrons (OIL, oxidation) or gains electrons (RIG, reduction) to achieve noble gas electron configuration Recognize the appearance of Bohr’s Model after an atom loses or gains electrons to form ions and/or how two atom share their electrons covalently to achieve noble gas electron configuration.

3. Supplemental packet page 50 Ionic Structure • • • • metal cation positive ion 2+ charge metal cation positive ion 1+ charge magnesium-24 ion sodium-23 ion • • 23 1+ 24 2+ Na Mg • • 12 11 • • • • combines w/ anions combines w/ anions • • • • • • • • 11 12 10 More protons than electrons [Na]1+ 1s2 2s2 2p6 3s0 12 12 10 More protons than electrons [Mg]2+ 1s2 2s2 2p6 3s0

4. Supplemental packet page 50 Ionic Structure • • • • • • • • • • nonmetal anion negative ion 2- charge metal cation positive ion 1+ charge nonmetal anion negative ion 1- charge metal cation positive ion 2+ charge magnesium-24 ion chloride-35 ion sodium-23 ion oxygen-16 ion • • • • • 23 1+ 35 1- 16 2- 24 2+ • Cl Mg Na O • • • • 11 8 12 17 • • • • • • • • • • combines w/ cations combines w/ cations combines w/ anions combines w/ anions • • • • • • • • • • • • • • • • • • • • • • • • • • [ ]1- O Cl • • • • • • • • [ ]2- 11 12 10 17 18 18 More protons than electrons More electrons than protons [Na]1+ 1s2 2s2 2p6 3s0 1s2 2s2 2p6 3s2 3p6 12 12 10 8 8 10 More protons than electrons More electrons than protons [Mg]2+ 1s2 2s2 2p6 3s2 1s2 2s2 2p6 3s0

5. Please note the movement of the red colored valence (outermost) electron on sodium. It is transferred over to the fluorine atom. Bohr Models Lewis dot structures

6. Please note the movement of the red colored valence (outermost) electron on the 1) _______ atom. It is transferred over to the 2) ________ atom. Fill in the blanks ANS. 1)Mg, 2)Cl

7. Record into your notes [Na]1+ 1s2 2s2 2p6 • • • • • • • • [ ]1- O Cl • • • • • • • • [Mg]2+ 1s2 2s2 2p6 [ ]2- 1s2 2s2 2p6 Ions isoelectronic (“same electronic configuration”) with noble gases [Ne] [Ar] 1s2 2s2 2p6 3s2 3p6 [Ne] [Ne]

8. Please note the addition of the red colored valence (outermost) electrons to each atom listed. Recognize boron, B, is a semimetal, not a nonmetal. semimetal nonmetals ions Draw the following into your notes opposite page 64 nonmetalsgain just enough electrons to achieve noble gas e- configuration of the noble gas in their period (row) • • • • • • • • • • C 4 – carbide ion N 3– nitride ion O 2– oxide ion F – fluoride ion Please Note: the nonmetals like to gain electrons & the stability of these ions is associated with 8 valence electrons (an octet)

9. Chapter 5 - Introduction to Chemical Bonding

10. [Na]1+ • • • • • • • • [ ]1- Electrostatic repulsions Like charges repel O Cl • • • • • • • • [Mg]2+ [ ]2- Electrostatic attractions Opposites attract Ions isoelectronic (“same electronic configuration”) with noble gases [Ne] [Ar] [Ne] [Ne]

11. Ionic Bonding (transferring electrons to achieve noble gas electron configuration) [Na]1+ • • • • • • • • • • • • • • • • [ ]1- [ ]1- [ ]1- Cl Cl Cl O [Mg]2+ • • • • • • • • • • • • • • • • [Mg]2+ [ ]2- 1.Opposites attract (cation attracts an anion) 2.Brought together by electrostatics 3.Ions coming together to balance charge sodium chloride magnesium chloride magnesium oxide

12. Looking ahead to Chapter 6 Covalent Bonding (sharing electrons to achieve noble gas electron configuration) 1. Bonding for FONCl BrISCH nonmetals 2. Brought together by sharing of electrons 3. Achieving an OCTET of valence electrons versus Chapter 5 - Ionic Bonding Ionic Bonding (transferring electrons to achieve noble gas electron configuration) 1. Opposites attract (cation attracts an anion) 2. Brought together by electrostatics 3. Ions coming together to balance charge

13. Please note the addition of the red colored valence (outermost) electron by the in coming hydrogen atom which will be shared by both atoms. H • H • H H H H • • • • • • • H H H • • H H Covalent Bonding (sharing electrons to achieve noble gas electron configuration) nonmetalsbondtohydrogen to achieve noble gas e- configuration of the noble gas in their period (row) Achieving an OCTET valence Addition of hydrogen CH4 methane gas NH3 ammonia gas H2O water HF hydrogen fluoride molecules of nonmetals hydrides Looking ahead to Chapter 6

14. [Na]1+ Ionic substances Supplemental packet page 64 • • • • [ ]1- Cl •• •• •• •• • • • • • • • • • • •• •• • • •• molecules of nonmetals hydrides •• 1+ 2+ 3+ 4- 3- 2- 1- 1 2 3 4 3 2 1

15. Supplemental packet page 64 To these molecules, Add missing nonbonding pair of electrons

16. •N O , nitrogen and oxygen may have variable number of bonds (2) (1) (4) (3) Favorite bonding modes for nonmetals C, N,O, halogen, H C N O F H •Know the preferred total number of bonds to these elements 4 3 2 1 1

17. Supplemental packet page 68 109.5 109.5 109.5 109.5 120 120 120 120 120 120 120 120 109.5 109.5 109.5 109.5 tetrahedral trigonal planar linear linear 107.5 107.5 q<120 pyramidal or trigonal pyramid bent 104.5 bent valence shell electron pair repulsion Ideal bonding for carbon = Four bonds to carbon - Four bonding modes 180 180 Ideal bonding angles for carbon Bond angles are less than ideal angle Electron pair occupies a lot of space & is held close to nucleus of central atom