PUTTING ATOMS TOGETHERChapter 7

TERMINOLOGYMolecule –

• Ex. Air = roughly 80% _______________ molecules, _____ oxygen molecules, and trace amounts of H2O and CO2

nitrogen 20%

two or more atoms of the same or different elements that are chemically joined together in a unit.

TERMINOLOGY

Chemical Formula –

• - small numbers written ____________, in chemistry usually indicates a charge • – small number ___________, tells us how many atoms there are

Diatomic Elements –

notation that indicates the type and number of atoms in a pure substance

Subscript

Superscript Mg2+

O2 = 2 oxygen atoms

above/after

below/after

Elements that exist as molecular elements consisting of 2 atoms.

* 7

MOLECULAR COMPOUNDSSharing is caring!

TERMINOLOGYMolecular Compounds – Compound consisting of two or more different elements with neutral charges that are bonded together. • Involves two _______________

(includes hydrogen) elements joining together and sharing their ________ electrons to fill their outer __________________ (shell).

non-metal

valenceenergy level

A simulation of the reaction: 2H2 + O2   ®    2H2O  

What do we call rxn’s that release energy/heat? What do we call rxn’s that require it?  

Illustration to the right shows two __________ molecules and a single _______ molecule. Hydrogen wants to have a full ________ shell (first shell can hold a max. of __) meanwhile the oxygen atom also wants to have a full valence shell (2nd shell can hold __). Therefore a ____________________ occurs.

hydrogen

oxygen

valence

8

2

sharing of electrons

2 H + 1 O H2O

Means electrons “LEAN” or migrate towards one molecule creating partial + and - charges

Forces that hold atoms together

Represent “potential” energy

A key aspect of molecular compounds is the fact they are ______________________ ____ ____________________. Only certain combinations in __________ _______________________ are found in nature. Ex.

•The above example highlights the fact that a change in ______________________________________ dramatically changes the ______________________________________________

dependent on arrangementfixed amounts

O2 = Oxygen Gas, meanwhile O3 = Ozone

configuration compound and how it affects us.

These molecules can be drawn as

__________________________________________ diagrams or as

____________________________________ with the shared pair of electrons

represented by a _____, 2 pairs by a ______, or 3 sets of shared

electrons by _____. The most that will ever be shared is 3.

Bohr-RutherfordLewis dot diagrams

IONIC COMPOUNDS

TERMINOLOGY

•Def.

• Involves a ___________ + a _____________ joining together, with the metal _____________ its ___________ _________ and the __________ taking them.

Def. Ion –_________________________________ 2 forms 1.) _________ = Positive 2.) _________ = Negative

Compound consisting of a positively charged (cation) and negatively charged (anion) ion.

metal giving away valence

electrons

non-metal

non-metal

a particle that has a + or - chargeCation Anion

WHY DOES THE METAL ALWAYS GIVE AWAY ITS VALENCE ELECTRONS AND THE NON-

METAL ALWAYS TAKE THEM?

•Think about this silently (use your notes or textbook as a reference)

ANSWER• It is easier for a metal to give up 3 or 4 electrons than try to take enough to fill its valence shell.

•For non-metals, they generally only need 1 or 2 extra’s to fill their shells, so it is easier for them to take 2 than give up 6.

  Sodium Atom, Na

Sodium Ion, Na+

Chlorine Ion, Cl-

Chlorine Atom, Cl

+ Charge (Protons)

       

- Charge (Electron)

       

Ionic charge        

DRAW DIAGRAM FROM TEXT(pg. 260)

• Copy the Bohr-Rutherford

• Create a Lewis Dot Diagram

Sodium Ion, Na+ Chlorine Ion, Cl-

HW Q 1-8 on page 261

PERIODIC TABLE WORKSHEET

REVIEW

1. _______ are located on the left side of the periodic table, with __________ located on the right side. They are separated by a “________” that touches the __________.

2. Horizontal rows are known as ________ and tell us the number of ______ _____ or ______ an element has.

Metals non-metals

staircasemetalloids

periodsEnergy levels shells

3. ________ or groups are vertical ________ on the periodic table and tell us how many valence _________ an element has.

4. ATOMS have the same number of Protons as they do ______ _______, so their charge is neutral, this information is detailed in the ______.

Families columns

electrons

atomic numbercharge

5. IONS have a positive or negative _______ because they have given up their _______ _________ or taken valence electrons from an atom of another element in order to fill/empty their outer energy shell.

6. Positive ions are known as _______ (think the t looks like a +) while negative ions are called _______ (has two n’s for negative).

chargevalence electrons

cationsanions

MAGNESIUM ATOM• Symbol = • Period # = •# of energy levels = •Group # = •# of Valence Electrons =•Member of the _____________ Family •Draw a Bohr-Rutherford Diagram

LITHIUM ATOM• Symbol = • Period # = •# of energy levels = •Group # = •# of Valence Electrons =•Member of the _____________ Family •Draw a Lewis-Dot Diagram

ARGON ATOM• Symbol = • Period # = •# of energy levels = •Group # = •# of Valence Electrons =•Member of the _____________ Family•Number of Neutrons = •Draw a Bohr-Rutherford Diagram

FLUORINE ATOM• Symbol = • Period # = •# of energy levels = •Group # = •# of Valence Electrons =•Member of the _____________ Family•Number of Neutrons = •Draw a Lewis Dot diagram

ION REVIEW a) An ION of fluorine is going to mimic (look like) an atom of ______.

b) An ION of beryllium is going to mimic an atom of __________________.

c) An ION of ____________ has to gain 3 electrons to mimic argon. Its ionic charge will be ____.

Neon

Helium

phosphorus-3

d) An ION of _________ has to give up 3 electrons in order to mimic an atom of neon. Its charge will be ___.

e) An Ion of Oxygen has to ____ ___ electrons to mimic _____. Its ionic charge will be ___.

gain 2-2neon

Aluminum

+3

CALCIUM ATOM• Symbol = • Atomic # = • # of Protons = • # of Electrons = • Ionic Charge = • Atomic Mass = • Number of Neutrons = • Draw a Bohr-Rutherford Diagram

OXYGEN ION• Symbol = • Atomic # = • # of Protons = • # of Electrons = • Ionic Charge = • Atomic Mass = • Number of Neutrons = • Draw a Bohr-Rutherford Diagram

CHLORINE ION• Symbol = • Atomic # = • # of Protons = • # of Electrons = • Ionic Charge = • Atomic Mass = • Number of Neutrons = • Draw a Bohr-Rutherford Diagram

ALUMINUM ION• Symbol = • Atomic # = • # of Protons = • # of Electrons = • Ionic Charge = • Atomic Mass = • Number of Neutrons = • Draw a Bohr-Rutherford Diagram

POTASSIUM ION• Symbol = • Atomic # = • # of Protons = • # of Electrons = • Ionic Charge = • Atomic Mass = • Number of Neutrons = • Draw a Bohr-Rutherford Diagram

QUESTIONS FROM READING• How do atoms become more stable? • When metals mix with another metal is it called an

________. • When metals mix with non-metals it is called an

__________ compound.• What happens with the electrons in these compounds?

• When two non-metals mix it is called an ____________ compound. • What happens with the electrons in these compounds?

IONIC COMPOUNDSNames & Formulas

REVIEW

•Def.

• Involves a ___________ + a _____________ joining together, with the metal _____________ its ___________ _________ and the __________ taking them.

Def. Ion –_________________________________ 2 forms 1.) _________ = Positive 2.) _________ = Negative

Compound consisting of a positively charged (cation) and negatively charged (anion) ion.

metal giving away valence

electrons

non-metal

non-metal

a particle that has a + or - chargeCation Anion

NAMINGIonic compounds are easily identified by the presence of a ___________ (first term). Any time you see a metal as the first term, you should automatically be thinking IONIC! Additionally, there is never a __________________ reference in the compound name (so no _________________). The nice thing about naming Ionic molecules is we __________ need to worry about numbers (subscripts).

metal

NUMERICAL

PREFIXESDO NOT

1)Determine how many elements (each capital letter represents a new element) are present in the compound (_______) and locate them on the periodic table. Is there a metal..? If so it must be a Ionic Compound.

2) Identify which of the elements is the metal (it must go first). __________________

3) Identify the non-metal element (it goes 2nd). ____________________

4) Write the name of the metal, than the name of the non-metal (but change the ending of the non-metal to “IDE”). ___________ _____________

Example K2O

2

Potassium

Oxygen

Potassium ox”ide’

Try these…

Li2O MgF2 NaCl K3N       

CaS Be3P2 LiBr Na2O       

Lithium oxide Magnesium flouride

Berylium phosphideCalcium sulphide

Sodium chloride

Lithium bromide

Potassium nitride

Sodium oxide

WRITING CHEMICAL FORMULAS FOR IONIC COMPOUNDS

Since the electrons are ____________ and electrical _______ are present we need to reference the Periodic Table in order to determine how many of each element there is going to be. ____________________________!

given/taken charges

THE CHARGES MUST BALANCE

Step 1: Locate the elements in the Periodic Table- ensure one is a metal, and one is a non-metal. Write down their chemical symbol.

Step 2: Determine the “charge” each element carries when its forms an ionic bond (remember: STABLE)

Step 3: Backcross the “charges“ to SUBSCRIPTS for each elementEx. Rubidiumfluoride

“charges it up” _____ _____ “backcross it down” Rb2O1

Rb O+1 -2

Rb O+1 -2

Compound

Sodium chloride

Magnesium nitride

Calcium fluoride

Francium phosphide

CHARGE       

FORMULA       

Na+1 Cl-1

NaCl

Mg+2 N-3

Mg3N2

Ca+2 F-1

CaF2 Fr3P

Fr+1 P-3