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Putting Atoms Together. Chapter 7. Terminology. two or more atoms of the same or different elements that are chemically joined together in a unit. . Molecule – Ex . Air = roughly 80% _______________ molecules, _____ oxygen molecules, and trace amounts of H 2 O and CO 2. nitrogen. - PowerPoint PPT Presentation
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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