Do Now!!! Two highly reactive elements in Period 4 are the metal potassium and the: Metalloid arsenic Nonmetal selenium Nonmetal bromine Nonmetal krypton

Do Now!!! Two highly reactive elements in Period 4 are the metal potassium and the: Metalloid arsenic Nonmetal selenium C. Nonmetal bromine Nonmetal krypton

Objectives Recognize stable electron configurations. Predict an element’s chemical properties using number of valence electrons and electron dot diagrams. Describe how an ionic bond forms and how ionization energy affects the process.

Chapter 6 Chemical Bonds

Stable Electron Configurations When the highest occupied energy level of an atom is filled with electrons, the atom is stable and not likely to react.

Electron Dot Diagram A diagram of an atom, ion or molecule in which each dot represents a valence electron.

Ionic Bonds A bond between a metal and a nonmetal. Some elements achieve stable electron configurations through the transfer of electrons between atoms. A bond between a metal and a nonmetal.

Do Now!!! In an ionic compound, the attractions between cations and _____________ hold the compound together. anions

Do Now!!! What is the name of CoCl2? Cobalt (II) chloride

Objectives Recognize stable electron configurations. Predict an element’s chemical properties using number of valence electrons and electron dot diagrams. Describe how an ionic bond forms and how ionization energy affects the process.

Na (sodium) loses 1 electron Cl (chlorine) gains 1 electron Transfer of Electrons Na (sodium) loses 1 electron Cl (chlorine) gains 1 electron

Ion An atom or group of atoms that has a positive or negative charge.

Anion An ion with a negative charge. Examples: Cl- (chloride ion) O2- (oxide ion)

Cation Examples: Na+ (sodium ion) Mg2+ (magnesium ion) An ion with a positive charge. Examples: Na+ (sodium ion) Mg2+ (magnesium ion)

Chemical Bond The force that holds atoms or ions together as a unit.

Ionic Bond The force that holds cations and anions together.

Ionization Energy

Ionization Energy The amount of energy needed to remove an electron from an atom. The lower the ionization energy, the easier it is to remove an electron from an atom.

Chemical Formula Examples: NaCl (sodium chloride) Notation that shows what elements a compound contains and the ratio of the atoms or ions of these elements in the compound. Examples: NaCl (sodium chloride) MgCl2 (magnesium chloride)

Crystals Sodium Chloride (salt) Crystal Solids whose particles are arranged in a lattice structure. Sodium Chloride (salt) Crystal

Properties of Ionic Compounds The properties of an ionic compound can be explained by the strong attractions among ions within a crystal lattice.

Do Now!!! The chemical formula for calcium chloride, CaCl2, shows that the compound contains two _____________ ions for every _____________ ion. chloride calcium

Objectives Describe how covalent bonds form and the attractions that keep atoms together in molecules. Compare polar and nonpolar bonds, and demonstrate how polar bonds affect the polarity of a molecule. Compare the attractions between polar and nonpolar molecules.

Covalent Bond A bond between a nonmetal and a nonmetal. A chemical bond in which two atoms share a pair of valence electrons. A bond between a nonmetal and a nonmetal.

Molecule A neutral group of atoms that are joined together by one or more covalent bonds.

Molecule Examples: HCl (hydrogen chloride) The attractions between the shared electrons and the protons in each nucleus hold the atoms together in a covalent bond. Examples: H2 (diatomic hydrogen) HCl (hydrogen chloride)

Covalent Bonds Double bond – share 4 electrons between 2 atoms Single bond – share only 2 electrons between 2 atoms Double bond – share 4 electrons between 2 atoms Triple bond – share 6 electrons between 2 atoms

Polar Covalent Bond A covalent bond in which electrons are not shared equally. When atoms form a polar covalent bond, the atom with the greater attraction for electrons has a partial negative charge. The other atom has a partial positive charge.

Polar and Nonpolar Molecules The type of atoms in a molecule and its shape are factors that determine whether a molecule is polar or nonpolar.

Attraction Between Molecules Attractions between polar molecules are stronger than attractions between nonpolar molecules.

Do Now!!! In an electron dot diagram, each dot represents a(an) _____________. electron

Objectives Recognize and describe binary ionic compounds, metals with multiple ions, and polyatomic ions. Name and determine chemical formulas for ionic and molecular compounds.

Describing Ionic Compounds The name of an ionic compound must distinguish the compound from other ionic compounds containing the same elements. The formula of an ionic compound describes the ratio of the ions in the compounds.

Nomenclature Group 1 and 2 metals and Al with non-metals 1. Metal name first 2. Non-metal name 2nd with the -ide ending

Nomenclature Examples: CaCl2 = calcium chloride K2S = potassium sulfide

Metals With Multiple Ions (P. 172) Many transitions metals form more than one type of ion.

Polyatomic Ion (P. 173) A covalently bonded group of atoms that has a positive or negative charge and acts as a unit. Name Formula Ammonium Hydroxide Nitrate Sulfate Sulfite Phosphate Chromate Silicate Cyanide Chlorate NH4+ OH- NO3- SO42- SO32- PO43- CrO42- SiO32- CN- ClO3- Acetate Peroxide Permanganate Hydrogen sulfate Hydrogen carbonate Hydrogen phosphate Dichromate Hypochlorite Carbonate Perchlorate C2H3O2- O22- MnO4- HSO4- HCO3- HPO42- Cr2O72- OCl- CO32- ClO4-

Metals with Polyatomic Ions Examples: Na2SO4 = Sodium sulfate Fe(NO3)3 = Iron(III) nitrate

Do Now!!! The name copper(II) indicates that a compound contains: copper ions with a 11+ charge. copper ions with a 2+ charge. copper ions with a negative charge. two types of copper ions.

Do Now!!! The name copper(II) indicates that a compound contains: copper ions with a 11+ charge. B. copper ions with a 2+ charge. copper ions with a negative charge. two types of copper ions.

Objectives Recognize and describe binary ionic compounds, metals with multiple ions, and polyatomic ions. Name and determine chemical formulas for ionic and molecular compounds.

Non-metals with non-metals (P. 175) Most electropositive element first 2. First element has a prefix indicating number and the name of the element EXCEPTION: Mono prefix (not used for first element) Second element has prefix indicating number and the “-ide” ending. NOTE: 2nd o is eliminated for oxides (e.g., monoxide not monooxide)

Non-metals with non-metals Examples: CO2 = Carbon dioxide BrF3 = Bromine trifluoride

Do Now!!! What is the name of TiO2? What is the formula of sodium phosphate? Titanium (IV) oxide Na3PO4

Objectives Recognize and describe binary ionic compounds, metals with multiple ions, and polyatomic ions. Name and determine chemical formulas for ionic and molecular compounds.

Metallic Bond The attraction between a metal cation and the shared electrons that surround it.

Metallic Bond The cations in a metal form a lattice that is held in place by strong metallic bonds between the cations and the surrounding valence electrons.

Properties of Metals The mobility of electrons within a metal lattice explains some of the properties of metals.

Manganese (III) cyanide Do Now!!! What is the name of Mn(CN)3? What is the formula of diboron trioxide? What is the formula of (NH4)2S? Manganese (III) cyanide B2O3 Ammonium sulfide

Do Now!!! An alloy that contains mainly copper and tin is: A. Sterling silver B. Brass C. Stainless steel D. Bronze

Do Now!!! An alloy that contains mainly copper and tin is: A. Sterling silver B. Brass C. Stainless steel D. Bronze

Objective Define an alloy and demonstrate how the composition of an alloy affects its properties.

Alloy A mixture of two or more elements, at least one of which is a metal, that has the characteristic properties of a metal.

Examples Brass: Copper and zinc Steel: Iron and carbon Bronze: Tin and copper Brass: Copper and zinc Steel: Iron and carbon Stainless Steel: Iron, carbon, and chromium

Objectives Predict the composition of an ionic compound from its chemical formula. Relate the properties of ionic compounds to the structure of crystal lattices.

Objectives Describe how covalent bonds form and the attractions that keep atoms together in molecules. Compare polar and nonpolar bonds, and demonstrate how polar bonds affect the polarity of a molecule. Compare the attractions between polar and nonpolar molecules.

Objectives Describe the structure and strength of bonds in metals. Relate the properties of metals to their structure. Define an alloy and demonstrate how the composition of an alloy affects its properties.