Unit 4 Review

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Unit 4 Review
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• Section 1 Forming Bonds
• 1) Why are noble gases unreactive?
• 2) Why do ions form?
• 3) What is the octet rule? How is it used?
• 4) Which is more likely to form a compound Mg
  or Ne? Why?
• 5) Why are the halogens and the alkali metals
  most likely to form ions?
• 6) How would the following elements achieve
  stability?
• Mg2_________ O2-___________
• C4/-_________ Na __________
• I1- __________ Xe _______

They have a full octet
To achieve a stable octet (8 valence electrons)
Atoms will gain/lose or share electrons to get 8
electrons. Used to predict ion formation.
Mg, because it does not have 8 valence electrons.
Because they only need one electron to be stable.
Lose 2 electrons
gain 2 electrons
Gain/ lose 4 electrons
Lose 1 electron
Gain 1 electron
none
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• 7) As potential energy (energy to react) goes
  down, stability goes _____________. When atoms
  complete their valence shell they gain stability
  and lost their potential energy. These
  reactions are ____________________________________
  , meaning they give off energy.
• 8) What is the charge on cations? ________Which
  is more likely to form a cation a metal or a
  nonmetal? Do cations form by gaining or losing
  electrons? Would they be smaller or larger than
  their neutral atom? _____________________________
  
• 9) What is the charge on anions? __________Which
• is more likely to form a anion a metal or a
• nonmetal? Do anions form by gaining or losing
  electrons? Would they be smaller or larger
• than their neutral atom? _______________________
  _______

up
exothermic

smaller
-
larger
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• 10) What is an ionic bond?
• 11) Describe how an ionic bond forms between
  sodium and chlorine.
• 12) Why dont we talk about ionic compounds as
  individual molecules?
• 13) What is another name for ionic compounds?
  ___________________
• 14) An ionic bond always forms between a
  __________________ a _________________.
• 15) What are the properties of salts? Know what
  causes each property.
• 1.
• 2.
• 3.
• 4.

Attraction between a cation and anion
Sodium loses one electron to chlorine Na Cl-
NaCl
Because we never have individuals they repeat
1000s of times in a crystal lattic
salts
Metal
Nonmetal
Hard and dense
brittle
High melting point
Only conduct when dissolved.
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NaCN

• Sodium cyanide _______________
• Aluminum hydroxide ____________
• Iron (III) oxide __________________
• Titanium (I) sulfide ______________
• Magnesium sulfide _____________
• Strontium phosphide ____________
• Lithium sulfide _________________
• Rubidium phosphate ____________

Al (OH)3
Fe2O3
Ti2S
MgS
Sr3P2
Li2S
Rb3PO4
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• Rubidium selenide _____________
• Barium iodide _________________
• Copper (II) hydroxide____________
• Manganese (IV) chloride _________
• Strontium acetate ______________
• Calcium sulfate _________________
• Mercury (I) nitride _______________
• Cesium nitride _________________

Rb2Se
BaI2
Cu(OH)2
MnCl4
Sr(C2H3O2)2
CaSO4
Hg3N
Cs3N
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calcium chloride

• CaCl2 ____________________________
• AgCl ____________________________
• K2S _____________________________
• CuO ____________________________
• Ba3N2 ____________________________
• FeN _____________________________
• MgBr2 ___________________________
• Fe3N2 ____________________________

silver chloride
potassium sulfide
copper (II) oxide
barium nitride
iron (III) nitride
magnesium bromide
iron (II) nitride
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ammonium chloride

• NH4Cl ____________________________
• AlPO4 ____________________________
• LiNO2 ___________________________
• Cs2SO3 __________________________
• FeCl3 ____________________________
• Cu2O____________________________
• Ti2O _____________________________
• Fe(NO2)2__________________________

aluminum phosphate
lithium nitrite
cesium sulfite
iron (III) chloride
copper (I) oxide
titanium (I) oxide
iron (II) nitrite
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• Metals are not ionic but DO share many properties
  with ionic compounds.
• 16. Name one similarity and one difference
  between ionic and metallic bonding.
• Describe the electron sea model of metallic
  bonding draw a picture.
• What physical properties does the electron sea
  model give metallic bonds?

Similarity attraction between positive and
negative ions Difference metals are malleable
and ionics are brittle
Positive metal cations have lost electrons to the
sea
Malleable and ductile Conductors Lustrous
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• 19. What is an alloy? Give two examples.
• 20. What characteristic of metallic bonds enable
  them to conduct electricity?

Any Mixture of metals Ex Steel- Mix of iron and
carbon
Delocalized electrons are free to move which is
how electricity is transferred
A mixture of metals Example steel mix of iron
and carbon