Chemistry Day 23 Tuesday, November 5th - Wednesday,

November 6th, 2019

Do-Now: “PT Quiz Review Do-Now” 1.  Write down today’s FLT 2.  What are valence electrons? 3.  Identify the group number, name, and number of

valence electrons for our four main representative groups

4.  Distinguish between transition metals and inner transition metals.

5.  Bob says that Na has a larger atomic radius than Cl. He says this is because Cl has more protons (17 versus 11), and therefore a greater effective nuclear charge that pulls electrons in closer, resulting in Cl’s smaller radius. What is MISSING from this explanation?

6.  Which has a bigger atomic radius and WHY: Na or Li? Be specific and descriptive.

7.  Take a few minutes to review your explanations for ALL of your trends.

Take out your planner and ToC

FLT •  I will be able to explain how anions and

cations form by completing Ions CN

Standard HS-PS1-1:Usetheperiodictableasamodeltopredicttherelativepropertiesofelementsbasedonthepatternsofelectronsintheoutermostenergylevelofatoms.

Ions

Recall

Valence Electrons

•  Valence electrons (ve-s) = e-s in the outermost shell (highest s and p orbitals) that can participate in chemical bonding

Valence Electrons •  Valence electrons à determine the

chemical properties of atoms •  These are located in the s and p orbitals

of the highest occupied energy level

Valence Electrons •  ve-s match the group number for

representative elements

Electron Dot Diagrams •  Lewis Dot Diagrams =

Notation for showing the ve-s for an atom or ion – Write symbol with valence e-s

surrounding – Hund’s rule – don’t double up

until you have to X

Electron Dot Diagrams

•  Ex/ •  F •  Ne •  N

Forming Ions

Recall •  Noble gases are inert gases – they are

highly unreactive •  Noble gases = have eight ve-s and

completely filled outer sublevels

The Octet Rule •  The Octet Rule = Elements gain or

lose e-s in order to obtain a noble gas configuration (8 ve-s or He 2ve-s) – Each noble gas (except He, which has 2) has 8

electrons in the outer level

Ions •  Atoms can gain or lose electrons to form

ions – Cations = (+) charged ions

• Ex/ Ca2+ – Anions = (-) charged ions

• Ex/ F-

Cations •  Metals lose their ve-s to form cations –  They form the configuration of the closest noble gas

that’s smaller than them

Na 1s22s22p63s1 – 1 valence electron

•  Na+1 1s22s22p6 – This is a noble gas configuration with 8 electrons

in the outer level.

Cations •  Examples

– K

– Ca

– Al

Cations •  Their charge should match their group

number

Subatomic Particles •  Be sure to account for the change in

electron number for ions •  Ex/ How many protons and electrons in…

Ca vs Ca+2

What are the e- configurations? •  Examples

– K+

– Al3+

Anions •  Nonmetals gain e-s to form anions

– They form the configuration of the closest noble gas that’s bigger than them

•  S = 1s22s22p63s23p4 – 6 valence electrons

•  S2- = 1s22s22p63s23p6 – noble gas configuration.

Anions •  Examples

– Br

– O

– N

Anions •  Group 7A: -1 •  Group 6A: -2 •  Group 5A: -3

What are their e- configurations? •  Examples

– Br-

– O2-

Formation of Anions

Pair-Share-Respond1.   Whatarevalenceelectrons?2.   Distinguishbetweenanionsand

cations3.   Howdometalsandnonmetalsform

ions?4.   Statetheoctetrule5.   Whatwouldbelargerandwhy:ForF-?

Chemistry Day 24 Thursday, November 6th – Friday,

November 7th, 2019

Do-Now: “Cat Inquiry Do-Now” 1.  Write down today’s FLT

2.  Define the terms anions and cations 3.  Why do atoms form ions? 4.  What ion will the Rb form? Show your work 5. Copy and complete: N has a ____ atomic radius

compared to C. Since both N and C have a principal quantum number of ___, this means that the ____ are the ____ and the e-s are at about the ____ distance from the nucleus. However, since N has ____ protons compared to C’s ____ protons, this means that the __________ between protons and e-s is stronger in ______, causing the electrons to be pulled ______ and the overall atomic radius is _______ than C’s.

6.  Turn in your ToC#2 if you haven’t already. Take out your planner and ToC

Video Clip • Wewillwatchavideoclipaboutcatsandballoons

•  Underneathyourdo-now…•  Useyourpro-talksentenceframe“Inmyopinion…because…”tomakeapredictionaboutwhatyouTHINKwillhappen.

Video Clip •  Now,writedownthreequestionsyouhaveaboutthevideo.

Video Clip •  Discussyourquestionswithyourgroup.•  Decideasagroupwhichquestionisthe“best”orthemostinteresting,andeveryoneshouldwriteitontheirpaper.

•  Pickaquestionthatshouldbeanswerableifgivensomeadditionalevidence.

•  Ifitisyourownquestion,placeastarnexttoit.

Video Clip •  Now,wewillwatchavideo.•  Duringthevideo,writedownoneortwopiecesofevidencethatcanhelpyouexplainwhat’shappening.

Video Clip •  Usetheinformationfromthevideotoansweryourquestion.

•  Useoneofthefollowingpro-talksentenceframes:– “FirstIconsidered…,then…____...Provesmyclaimbecause…”

– “Ifwelookatboth….and….Wecanseethat….”

– “Basedontheevidence,wecanconcludethat….”

FLT •  I will be able to write the formulas and

describe properties of ionic compounds by completing Ionic Bonding CN

Standard HS-PS1-1:Usetheperiodictableasamodeltopredicttherelativepropertiesofelementsbasedonthepatternsofelectronsintheoutermostenergylevelofatoms.

Ionic Bonding

Recall

The Octet Rule •  The Octet Rule = Elements gain or lose

e-s in order to obtain a noble gas configuration (8 ve-s or He 2ve-s)

Ions •  Atoms can gain or lose electrons to form

ions – Metals lose e-s to form cations

• Ex/ Ca2+ – Nonmetals gain e-s to form anions

• Ex/ F-

Ions •  What charges would the following atoms

have if they became ions? – Na – Cl – F – Ba – Ca – O

Compounds

Compounds •  So far, we have been looking at atoms

by themselves •  Compounds = substances made of

atoms of 2+ elements chemically combined in fixed ratios

Examples: NaCl CaF2 H2O

Mg(OH)2

Compounds •  Compounds are held together by

chemical bonds such as ionic bonds, covalent bonds, and more!

CH4

Ionic Bonding

Ionic Bonding •  Anions and cations are held together by

opposite charges (+ and -) •  Ionic Bond = Strong electrostatic

attraction between an anion and cation

Ionic Bonding •  Salts = Ionic compounds (ex/ NaCl)

– Formed through the transfer of e-s

Ionic Bonding •  Also called SALTS •  Made from: a CATION with an ANION

– or literally from a metal (+) combining with a nonmetal (-)

Ionic Bonding

•  The metal (sodium) tends to lose its one electron from the outer level.

•  The nonmetal (chlorine) needs to gain one more to fill its outer level, and will accept the one electron that sodium is going to lose.

Na Cl

Writing Formulas

Writing Formulas •  Metals are always written 1st

– Ex: NaCl vs ClNa

Writing Formulas •  When ions have equal and opposite

charges, they bond together in a 1:1 ratio – Ex: Na and F

– Ex: Mg and S

– Ex: Al and P

Writing Formulas •  The charges of ions in a chemical

formula must always sum to 0 •  What happens if the charges are not

equal and opposite? – Ex/ Calcium and Fluorine

Writing Formulas •  If ions do not have the same charge, you

must find the lowest common multiple – Ex/ Ca and F

Writing Formulas •  If ions do not have the same charge, you

must find the lowest common multiple – Ex/ Mg and P

Do-Now •  Write the following formulas:

a. Mg and O

b. Li and F

c. Li and S

d. Mg and S

e. Ca and N

Properties of Ionic Compounds 1.  Ionic solids have crystalline

structures - a regular repeating arrangement of ions in the solid

–  Ions are strongly bonded together. –  Structure is rigid, but brittle

Coordination Numbers:

Both the sodium and chlorine have 6

Both the cesium and chlorine have 8

Each titanium has 6, and each oxygen has 3

NaCl

CsCl

TiO2

Coordination number- number of ions of opposite charge surrounding it

Properties of Ionic Compounds 2.  High melting points •  It requires a lot of energy to change

from a solid to a liquid •  High boiling point as well

Do they Conduct?

•  Conducting electricity means allowing charges to move.

•  In a solid, the ions are locked in place. •  Ionic solids are insulators. •  When melted, the ions can move around. 3.  Melted ionic compounds are

conductors. –  NaCl: must get to about 800 ºC. –  Dissolved in water, they also conduct (free

to move in aqueous solutions)

Pair-Share-Respond1.   Whatarecompounds?2.   Definetheterm“ionicbond”3.   Howareionicbondsformed?4.   PredicttheformulaforAluminumand

Oxygen