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Bell Ringer. What types of chemical bonds exist?. Beanium Finish Fireworks Heinz 57. Bell Ringer. How many valence electrons do atoms want to obtain?. Chemical Bonding. A bond is the electrostatic force of attraction between two particles (atoms, ions or molecules). Why/How Bonds Formed?.
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Bell Ringer What types of chemical bonds exist?
Beanium Finish Fireworks Heinz 57
Bell Ringer How many valence electrons do atoms want to obtain?
Chemical Bonding A bond is the electrostatic force of attraction between two particles (atoms, ions or molecules)
Why/How Bonds Formed? • They are formed/broken during Chemical Reactions • Formed = release energy • Broken = absorb energy
Why form a bond? Valence Electrons - want to achieve happiness “Octet Rule” - want a full valence shell = HAPPY!
Types of Bonds Atoms Involved Ionic Covalent Metallic - metal and nonmetal - nonmetal + nonmetal - metal + metal
Naming Compounds Jump Jump
Kriss-Kross will make you... Find the correct formula for a compound!! • Use the oxidation #’s • Put the positive one first H+1 + O-2 H2O
Criss-Cross practice +2 -1 CaBr2 Ca + Br +2 -1 Mg+ (OH) Mg(OH)2 +2 -2 Sr2O2 SrO Sr + O
Criss-Cross practice +1 -2 Na2Se Na + Se +3 -1 Fe(HCO3)3 Fe (III)+ (HCO3) +3 -3 Al + PO4 Al3(PO4)3 Al(PO4)
Bell Ringer What would the oxidation number be for Iron in the following compounds: Fe2O3 FeS
Bell Ringer What are the formulas for the compounds between: Oxygen and Phosphorus Iodine and Barium
H2O Bonding Atoms combine to form compounds By bonding atoms together, their properties change I. Bonding H2 O2 A.Chemical Bond This is the attractive force between atoms or ions Results from the rearrangement of valence electrons B. Energy Changes As a chemical bond forms, atoms are brought to a lower energy state Free atoms have more energy than bonded atoms
Naming Ionic Compounds Remember: A bond between a metal and a non-metal atom The metal keeps its name, and the non-metal ends in -ide KBr CaCl2 Potassium Bromide Calcium Chloride
Naming Ionic Compounds When you have more than two elements, refer to Ref. Table E. Sodium Hydroxide NaOH (NH4)(NO2) Ammonium Nitrite KMnO4 Potassium Permanganate
Labs Practice Kriss-Kross
Bell Ringer What are the names of the following compounds: KCH3COO BaCr2O7
+ - Bonding As we said before, atoms can bond together by moving their valence electrons around Actually, atoms can either lose, gain or share electrons. This gives us several types of bonds e- e- e- e- e- Bonds between Atoms Ionic Bond Atoms transfer electrons Creates ions Forming ions An ion is formed when atoms lose or gain electrons Ion = Charged atom due to a loss or gain of electrons
As pure elements, these seven elements form molecules containing two atoms HON – 17 Diatomic Molecules 3 H2 N2 O2 F2 Cl2 Br2 I2
As pure elements, these seven elements form molecules containing two atoms HON – 17 Diatomic Molecules 3
Quiz 1. Barium Sulfate 2. CaO 3. Potassium Oxide 4. Na2CO3 5. Magnesium Oxide
Quiz 6. SrCrO4 7. Barium Chloride 8. NaNO3 9. MgSO4 10. Beryllium Sulfite
Bell Ringer What are the names of the following compounds: CoI3 MgSO4
meow. Sodium Atom Chlorine Atom +11 -11 -10 +17 -17 -18 +1 -1 0 Total charge 0 Total charge a negative ion neutral Atom is considered neutral a positive ion Atom is considered Called an Anion Called a Cation In an ionic bond, one electron from sodium is transferred to chlorine Cation Positive ion due to the loss of electrons Anion Negative ion due to the gain of electrons Are you positive you lost the cat?
Examples - Determine the type of ion shown and explain how it was made from a neutral atom. Ion Type of Ion How it was made K+ Ca+2 O-2 Br- cation Lost 1 electron cation Lost 2 electrons anion Gained 2 electrons anion Gained 1 electron
Draw the electron dot formula for neutral atoms of Na and F 2 8 1 + - Na F All atoms want a full octet in their valence shell. This is a stable configuration. When ionic bonding occurs,the one valence electron in Na is transferred to F + Notice how both atoms have a full octet? Na F has gained an electron to get a total of 8. Na uses its full shell underneath as a full valence The attraction between the + and - ion causes the bond Review Ionic bonds 1. Electrons are transferred 2. Ions are created Cation lost e-,anion gained e- 3. Very strong bond. Has high melting and boiling points, and a very rigid structure 4. Creates ionic substances
H H H H Covalent Bonds a. Electrons in bonds - No transfer of electrons - Electrons are shared between valence shell of atoms - Weaker bonds than ionic In covalent bonding, atoms get a full octet by sharing electrons between their valence shells Special Case Hydrogen and helium do not need 8 electrons, only 2 So the molecule H2 looks like
Bell Ringer What are the formulas for the following compounds: Sodium thiocyanate Ammonium oxide
Covalent Bonds In covalent bonding, atoms still want to achieve a noble gas configuration The octet rule But rather than losing or gaining electrons, atoms now share an electron pair. The shared electron pair is called a bonding pair
Chlorine forms a covalent bond with itself • Cl2
How will two chlorine atoms react? Cl Cl
Cl Cl Each chlorine atom wants to gain one electron to achieve an octet
Cl Cl Neither atom will give up an electron – chlorine is highly electronegative. What’s the solution –what can they do to achieve an octet?
Cl Cl
Cl Cl
Cl Cl
Cl Cl
Cl Cl octet
Cl Cl octet circle the electrons for each atom that completes their octets
Cl Cl The octet is achieved by each atom sharing the electron pair in the middle circle the electrons for each atom that completes their octets
Cl Cl The octet is achieved by each atom sharing the electron pair in the middle circle the electrons for each atom that completes their octets
Cl Cl This is the bonding pair circle the electrons for each atom that completes their octets
Cl Cl It is a single bonding pair circle the electrons for each atom that completes their octets
Cl Cl It is called aSINGLE BOND circle the electrons for each atom that completes their octets
Cl Cl Single bonds are abbreviated with a dash circle the electrons for each atom that completes their octets
Cl Cl This is the chlorine molecule, Cl2 circle the electrons for each atom that completes their octets
O2 Oxygen is also one of the diatomic molecules
O O How will two oxygen atoms bond?