Compounds and Bonding Ms. Pici 2016-2017

MEMORY BOX WRITE DOWN EVERYTHING YOU CAN REMEMBER ABOUT PARTICLES IN AN ATOM, THE PERIODIC TABLE, BOHR AND LEWIS DOT DIAGRAMS,ETC

MEMORY BOX

VOCABULARY DEFINITION EXAMPLE/PICTURE COMPOUND 2 or more elements chemically combined in a ratio.   H2O CHEMICAL FORMULA “Recipe” for a compound. (type of element and how much of each exists) 2 parts H + 1 part O = H2O SUBSCRIPT Number written below to show ratio Subscript VALENCE SHELL Outermost shell (energy level) VALENCE (LAST SHELL)

Cl2 CO2 NaCl Al2(NO3)3 PRACTICE: Tell how many atoms of each element there are in these compounds below:   Cl2 CO2 NaCl Al2(NO3)3

PRACTICE: Tell how many atoms of each element there are in these compounds below:   Cl2 2 atoms of Cl CO2 1 carbon, 2 oxygen NaCl 1 sodium, 1 chlorine Al2(NO3)3 2 aluminum, 3 nitrogen, 9 oxygen

Note: when the subscript appears outside the parentheses, you multiply the number of atoms of each element inside the parentheses by the number outside the parentheses. Quizzical questions: What does the absence of a subscript after a symbol means? What do all the elements want that the noble gases already have?

Quizzical questions: What does the absence of a subscript after a symbol means? Only one of that kind of element in the formula (ONE ATOM) What do all the elements want that the noble gases already have? A full valence shell “8”

Knowing this, answer the following questions about METALS. When an element loses an electron, it has a positive charge. Look up Mg on the periodic table and what does it say in the upper right hand corner? +2 Why do you think it says that? Mg lost 2e-, metals lose e- and e- are negative.

Knowing this, answer the following questions about NONMETALS. When an element gains an electron, it has a negative charge. Look up S on the periodic table and what does it say in the upper right hand corner? -2 Why do you think it says that? Sulfur gained 2e-

**** What is the benefit of a METAL bonding with a NONMETAL? Both metal and nonmetal get a full valence shell “8” (give/get).

Define OXIDATION #: change (+,-) from gain/loss of electrons Ionic Bonding Define IONIC BOND: between positive and negative; between a metal and a nonmetal; strong bond; transfer (gives/gets) Define OXIDATION #: change (+,-) from gain/loss of electrons

Ionic Bonding Review An ionic bond only happens between a metal and a nonmetal. An ionic bond involves charged particles called ions. An ionic bond is a strong bond because opposites attract. An ionic bond requires that the metal lose electrons and the nonmetal gain electrons.

Define COLVALENT BOND: 2 nonmetals; Sharing of valence e- ; weaker Covalent Bonding Define COLVALENT BOND: 2 nonmetals; Sharing of valence e- ; weaker

Elements Combined Types of Element Electron Dot Diagram Formula   H and O Nonmetal H₂O S H₂S C Cl CCl₄ CO₂

Covalent Bonding Review A covalent bond only happens between a nonmetal and a nonmetal. A covalent bond involves sharing of electrons. A covalent bond is a weaker bond because electrons are shared, not transferred. The smallest part of a covalent compound is called a molecule.

Compare/Contrast Ionic and Covalent Bond IONIC BOND CONCEPT COVALENT BOND   Metal & Nonmetal Formed between Nonmetal & Nonmetal Give/ Get Gaining & Losing How bond is formed Sharing Stronger Strength of bond Weaker

THINK ABOUT THE TWO TYPES OF BONDS AND IDENTIFY: THREE SIMILARITIES Nonmetals in both Ionic and Covalent bonds. Valence electron shell is full. Two or more elements. Form compounds.   ONE IMPORTANT DIFFERENCE Ionic bonds contain metals. Ionic bonds require valence (eˉ) to be transferred (not shared).

Identify the following compounds as either ionic or covalent and give a reason for your identification.

Identify the following compounds as either ionic or covalent and give a reason for your identification. COMPOUND IONIC OR COVALENT REASON H₂SO₄ Covalent All nonmetals CaF₂ Ionic Ca – metal; F – nonmetal Al₂O3 Al – metal; O - nonmetal

What does the prefix “Bi” mean (hint…think bicycle)? 2 Knowing that, what do you think is meant by a “binary compound”? Two element’s in a compound. Would salt be a binary compound? Why or why not? NaCl – yes, it’s made of two elements.

All binary compounds are named by leaving the name of the first element alone and changing the name of the second element to “ide”. Give it a try.

COMPOUND FORMULA NAME   NaCl Sodium Chloride CuO Copper Oxide CaBr Calcium Bromide PbS Lead Sulfide KI Potassium Iodide