Chapter 6 Chemical Bonds

6.1 Ionic Bonding Stable Electron Configurations ▫When the highest occupied energy level of an atom is ______ with electrons, the atom is ____ and will ___ react.  Ex: _________(8 valence electrons) and ______ (2 v.e.)

Electron Dot Diagrams Electron Dot Diagrams (_____________) is a model of an atom in which each ___ represents a ________________

Ionic Bonds Elements that do not have complete sets of valence electrons will be _______. By reacting, they can achieve __________ sets. Some elements achieve stable electron configurations through the ________ of electrons between atoms.

Formation of Ions When an atom gains or loses an electron, the protons ______equal the electrons. The atom is no longer ________. _____- Atom that has a net positive or negative charge. ▫_____- Ion with a ________ charge.  To name an anion, you change the suffix to –ide and add ion.  Ex: ▫_____- Ion with a ________ charge.  To name a cation, you add ion to the end.  Ex:

Formation of Ionic Bonds Chemical Bond- ____ that holds atoms or ions together. Ionic Bond- force that holds _____________together. ▫An ionic bond forms when electrons are ___________ from one atom to another ___________-the amount of energy needed to remove an ________. ▫The _____ the ionization energy, the easier it is to _____ an electron.  It’s easier to remove an electron from a _____ than from a nonmetal

Ionic Compounds A chemical formula is a notation that shows what elements a compound _______ and the ____ of the atoms or ions of these elements in the compound. ▫Ex:

Ionic Compound Diagrams to try: K and Cl Li and S Sr and ClAl and N *Ga and S

Crystal Lattices Remember that orderly, 3-D structure of solids? ▫In NaCl, each chloride ion is surrounded by 6 sodium ions and each sodium ion is surrounded by 6 chloride ions. ▫The ________ charges keep ions in their fixed positions in a rigid framework, or ________. _______- Solids whose particles are arranged in a lattice structure.

Properties of Ionic Compounds The properties of an ionic compound can be explained by the _____________among ions. ▫____ melting point ▫____ conductor of electricity when solid, ____ conductor when melted. ▫______ when struck by a hammer

6.2 Covalent Bonds Sharing Electrons ▫H has __ electron. If it had ___ electrons, it would be happy. (It would have a full outer energy level.) ▫Two H atoms can ____ their electrons Covalent Bond- chemical bond in which 2 atoms ____ a ____ of valence electrons. ▫When two atoms share 1 pair of electrons, the bond is a _________

Molecules of Elements Two hydrogen atoms bonded together form a unit called a _________ Molecule- ________ group of atoms that are joined together by one or more _______ bonds The ________ between the shared electrons and the protons in each _______ hold the atoms together in a covalent bond.

Diatomic Molecules & Multiple Covalent Bonds ___________- occurs in many nonmetals. It’s two atoms of the same element. ▫Ex: ▫HONClBrIF Multiple Covalent Bonds Nitrogen has 5 valence electrons. It needs to share ______of electrons in order to be happy.

Unequal Sharing of Electrons In general, elements on the right of the periodic table have a _______ attraction for electrons. ▫_________ has the strongest attraction. Polar Covalent Bonds ▫Electrons are ___ shared equally. Ex: ▫Electrons will hang out by __, giving it a slight _______ charge. The other atom will have a slight ______ charge. Shared electrons in a hydrogen chloride molecule spend less time near the hydrogen atom than near the chlorine atom.

Nonpolar Covalent Bonds ▫Electrons are shared ______.  Polar molecules have stronger attractions to each other.

6.3 Naming Compounds and Writing Formulas Naming Ionic Compounds ▫Binary Ionic Compounds – Made from only _ elements – 1 ____ and 1 _________  _____ first followed by _____.  Change the ending of the anion to -___

6.3 Naming Compounds and Writing Formulas Writing Formulas for Ionic Compounds ▫Place the ______ of the cation first, followed by the _____ for the anion. ▫Use ________to show the ratio of the ions in the compound (all compounds must be ______)  Use ___________ method

6.3 Naming Compounds and Writing Formulas Naming Molecular Compounds ▫The ______ element appears first. ▫The name of the second element changes its ending to –____.  Ex: ▫Use the Greek prefixes to reflect the _________ of atoms of each __________  Ex: ▫If ____ appears in the first element, the prefix is ______.  Ex: NO 2 mononitrogen dioxide becomes_________ __________________

6.3 Naming Compounds and Writing Formulas Writing Molecular Formulas ▫Write the symbols for the elements in the order the elements _______ in the _____ ▫________ indicate the number of atoms of each element – they become __________  If there is no prefix, there is only ___ atom  Ex: Diphosphorus tetrafluoride ______

6.4 The Structure of Metals Remember, metals like to____electrons. What happens if no _______ are present to accept the extra electrons? ▫In a metal, valence electrons are ____ to move along the atoms. ▫Metal atoms become ______ surrounded by a “__________________” _________-the attraction between a metal cation and the shared electrons that surround it. ▫The cations in a metal form a _____ that is held in place by the strong _________between cations and the surrounding valence electrons. ▫Overall, a metal is _______ because the total number of __________ does not change.

The sea of valence electrons can explain the various properties of metals 1. Alkali metals are very ___. The bonds between the cations and the electrons are very ___ because each metal only contributes __ valence electron. 2. An electric current is a flow of charged particles. Metals have a _______ flow of charged particles. 3. Metals are _______. When metal is struck with a hammer, the metal ions ____ their position and the shape ________ In a metal, cations are surrounded by shared valence electrons. If a metal is struck, the ions move to new positions, but the ions are still __________ by electrons.

Alloys Gold is a ___ metal. It becomes harder when _____ with Ag, Cu, Ni, or Zn ______ – A mixture of two or more elements, at least one of which is a _____. ▫Alloys have the characteristic properties of _____. ▫EX:  Gold that is 100 percent pure is labeled _______ gold.  Gold jewelry that has a 12-karat label is only __ percent gold.  Jewelry that has an 18-karat label is ___ percent gold.