Section 11.1 Atoms and Energy Chemical Bonds The forces that hold together atoms in molecules are called chemical bonds. –Three main types of bonds 1.Ionic bonds: Electron Transfer 2.Covalent bonds: Electron Sharing 3.Metallic Bonding: Electron “Sea”

Section 11.1 Atoms and Energy Valence electrons are those electron residing in the outermost shell; this is where chemical bonding takes place!!

Section 11.1 Atoms and Energy Lewis Dot Structures: Valence electrons

Section 11.1 Atoms and Energy Valence Electrons & Ionization Non-metals will gain electrons to fill their current orbital, becoming more negative

Section 11.1 Atoms and Energy Valence Electrons & Ionization Metals will lose electrons to have a full orbital from a lower level, becoming more positive

Section 11.1 Atoms and Energy C. Atomic Properties and the Periodic Table Metals and Nonmetals Metals tend to lose electrons to form positive ions. Nonmetals tend to gain electrons to form negative ions.

Section 11.1 Atoms and Energy Predict the Bond Type Chemical CompoundType of Bond N2N2 NO 2 BaBr 2 FeO Fe (s) CF 4 CH 2 O ZnCl 2

Section 11.1 Atoms and Energy B. Ionic bonding and Structures of Ionic Compounds Cations are always smaller than the parent atom Structures of Ionic Compounds Anions are always larger than the parent atom

Section 11.1 Atoms and Energy B. Ionic bonding and Structures of Ionic Compounds Ions are packed together in a crystal lattice with an arrangement that maximizes the electrostatic attraction between ions Structures of Ionic Compounds

Section 11.1 Atoms and Energy

Section 11.1 Atoms and Energy Covalent Bonds A covalent bond forms when electrons are shared. Non-metals bond covalently with other ELECTRONEGATIVE non-metals

Section 11.1 Atoms and Energy Covalent Bonds Q: How might Carbon and Hydrogen share electrons to make a filled orbital configuration? EX. Hydrogen EX. Carbon H C

Section 11.1 Atoms and Energy Covalent Bonds Q: How might diatomic Hydrogen share electrons to make a filled orbital configuration? How about Oxygen and Hydrogen? EX. Hydrogen EX. Oxygen H O

Section 11.1 Atoms and Energy Predict the Bond Type Chemical CompoundType of Bond N2N2 NO 2 BaBr 2 FeO Fe (s) CF 4 CH 2 O ZnCl 2

Section 11.1 Atoms and Energy Metallic Bonding Atomic Solids Have atoms as their fundamental particle –Pure metals (Au, Ag, Zn, etc.) The atoms are difficult to separate (ductility, malleability) but can easily slide past each other Electron Sea Model: An array of metal atoms with mobile valence electrons shared in a non-directional way Non-directional strong bonding A metal crystal

Section 11.1 Atoms and Energy Predict the Bond Type Chemical CompoundType of Bond N2N2 NO 2 BaBr 2 FeO Fe (s) CF 4 CH 2 O ZnCl 2

Section 11.1 Atoms and Energy C. Atomic Properties and the Periodic Table Atomic Size Size tends to increase down a column. Size tends to decrease across a row.

Section 11.1 Atoms and Energy Trends in Ionization Energies: Removing ONE electron

Section 11.1 Atoms and Energy Trends in Ionization Energies: Removing ONE electron

Section 11.1 Atoms and Energy B. Electronegativity: Electron Affinity Electronegativity – the relative ability of an atom in a molecule to attract shared electrons to itself –Quantitative scale –Follows the same trends as ionization energy –The higher an atom’s electronegativity value, the closer the shared atoms tend to be to that atom when it forms a bond.

Section 11.1 Atoms and Energy ELECTRONEGATIVITY = Electron Affinity

Section 11.1 Atoms and Energy B. Electronegativity

Section 11.1 Atoms and Energy B. Electronegativity The polarity of a bond depends on the difference between the electronegativity values of the atoms forming the bond As a general rule, if the difference in EN values is > 2.0, then the bond is considered to be ionic.

Section 11.1 Atoms and Energy

Section 11.1 Atoms and Energy

Section 11.1 Atoms and Energy

Section 11.1 Atoms and Energy

Section 11.1 Atoms and Energy GREEN SHEETS: Covalent