Nomenclature Ionic, Covalent, Acid Unit 5: Formulas, Part 2 Nomenclature Ionic, Covalent, Acid Log in with your Clicker!

Unit 5: Formulas, Part 2 Nomenclature! (Is a fancy word for naming things) There are 3 types of compounds you need to know how to name & write formulas for: Ionic (we already learned that!) Molecular (aka Covalent) Acid (a special type of covalent)

A. Ionic FORMULAS Review Write each ion, cation first. Don’t show charges in the final formula. Overall charge must equal zero. If charges cancel, just write symbols. If not, use subscripts to balance charges. Use parentheses to show more than one polyatomic ion. Roman numerals indicate the ion’s CHARGE

A. Ionic NOMENCLATURE Write the names of both ions, cation first. Change ending of monatomic ions to -ide. Polyatomic ions have special names. Don’t change polyatomic endings! Use Roman numerals to show the metal’s positive charge (except s-block, Ag, Zn, Al). Overall charge must equal zero. Charge balance!

A. Ionic Nomenclature Consider the following: Does it contain a polyatomic ion? -ide, 2 elements  no -ate, -ite, 3+ elements  yes Does it contain a Roman numeral? Check its location on the periodic table– Roman #’s are required for metals not in Groups 1 or 2 (s-block) or Ag, Zn, Al. No numerical prefixes!

Valence Electrons & Stability Main Group Ion Charges 1+ 2+ 3+ 4± 3- 2- 1-

A. Ionic Formula Review potassium chloride magnesium nitrate copper(II) chloride K+ Cl-  KCl Mg2+ NO3-  Mg(NO3)2 Cu2+ Cl-  CuCl2

A. Ionic Nomenclature Review Name each compound: NaBr Na2CO3 FeCl3 sodium bromide sodium carbonate iron (III) chloride

B. Molecular Nomenclature Prefix System (binary compounds) Name first element. Name second element. 2. Add prefixes to indicate # of atoms. Omit mono- prefix on first element. 3. Change the ending of the final element to -ide.

B. Molecular Nomenclature PREFIX mono- di- tri- tetra- penta- hexa- hepta- octa- nona- deca- NUMBER 1 2 3 4 5 6 7 8 9 10

B. Molecular Nomenclature CCl4 N2O SF6 carbon tetrachloride dinitrogen monoxide sulfur hexafluoride

B. Practice! Give the subscripts arsenic trichloride dinitrogen pentoxide tetraphosphorus decoxide As1Cl3 N2O5 P4O10

B. Molecular Nomenclature Remember the Seven Diatomic Elements! Br2 I2 N2 Cl2 H2 O2 F2 H N O F Cl Br I

C. ACIDS! Acids Compounds that release H+ in water. Formulas generally begin with ‘H’. Examples: HCl – hydrochloric acid HNO3 – nitric acid H2SO4 – sulfuric acid

We are learning two types of acid: C. Acid Nomenclature We are learning two types of acid: Binary acids (only two elements) HBr Ternary acids (three or more elements) H2SO4

Binary acids (only two elements) C. Acid Nomenclature Binary acids (only two elements) hydro____ic acid HBr  hydrobromic acid H2Se  hydroselenic acid

C. Acid Nomenclature Ternary acids or oxoacids (three elements) Are formed from polyatomic ions. “ate” ions make “ic” acids “ite” ions make “ous” acids H2CO3 CO32- = carbonate ion  carbonic acid H2SO3 SO32- = sulfite ion  sulfurous acid

C. Acid Nomenclature (based on a polyatomic ion)

C. Acid Nomenclature (monatomic ion ending) (binary acid) (polyatomic ion ending) (ternary acid) (polyatomic ion ending) (ternary acid)

C. Acid Nomenclature Practice Name the following acids: H3PO4 (a) hydrophosphic acid (b) hydrophosphorous acid (c) phosphoric acid (d) phosphorous acid HNO2 (a) hydronitric acid (b) hydronitrous acid (c) nitric acid (d) nitrous acid HF (a) hydrofluoric acid (b) hydrofluorous acid (c) fluoric acid (d) fluorous acid H3PO4 (a) hydrophosphic acid (b) hydrophosphorous acid (c) phosphoric acid (d) phosphorous acid HNO2 (a) hydronitric acid (b) hydronitrous acid (c) nitric acid (d) nitrous acid HF (a) hydrofluoric acid (b) hydrofluorous acid (c) fluoric acid (d) fluorous acid

C. Writing Acid FORMULAS The two kinds of acids have different rules for writing formulas. Binary Identify them: The name begins with “hydro”

C. Acid FORMULAS Ternary The two kinds of acids have different rules for their formulas. Ternary Identify them: The name does not begin with “hydro”

We call this “charge balancing” the compound. C. Acid FORMULAS Two rules are true for both types of acid: The formula begins with the element H. You need to add subscripts to make the overall charge of the compound = 0 We call this “charge balancing” the compound.

C. Acid FORMULAS hydrofluoric acid H & F H1+ F1- H1F1 Must be binary because its name begins with “hydro” Two elements: Find their ion charges from periodic table: Add subscripts to charge balance the compound. H & F H1+ F1- H1F1 (Balance by finding the LCM, just like with ionic compounds.)

C. Acid FORMULA practice Write a formula for: hydronitric acid How many elements? What are they? What are the subscripts on the formula? 2 elements (binary) hydrogen & nitrogen H1+ N3-  H3N1

C. Acid FORMULAS nitric acid Nitric acid is ternary. NO3- HNO3 Must NOT be binary because its name does not begin with “hydro.” Nitric acid is ternary. Ternary acids are based on polyatomic ions: NO3- HNO3 (Remember, these are listed on the back of your periodic table.)

C. Acid FORMULAS To write a ternary acid, you must identify the polyatomic ion it contains. Ternary Acids have two possible endings: “-ic acid” Is based on an “-ate” polyatomic ion. (sulfate, nitrate, carbonate, etc)

C. Acid FORMULAS To write a ternary acid, you must identify the polyatomic ion it contains. Ternary Acids have two possible endings: “-ic acid” Is based on an “-ate” polyatomic ion. (sulfate, nitrate, carbonate, etc) “-ous acid” Is based on an “-ite” polyatomic ion. (sulfite, hypochlorite, nitrite, etc.)

C. Acid FORMULA practice sulfuric acid How many elements? Which polyatomic ion? From the chart: Add H1+ to the front, then charge balance: ternary = 3 elements The acid contains a polyatomic ion! An “-ic acid” comes from “-ate” ion sulfur + “-ate”  sulfate ion sulfate ion = SO42- H1+ SO42-  H2SO4

C. Acid FORMULA practice Oxalic Acid (a) binary or (b) ternary How many hydrogens does it contain? Hypochlorous acid How many hydrogens does it contain? (b) ternary (no hydro) oxalate = C2O42- 2  H2C2O4 (b) ternary (no hydro) hypochlorite = ClO-  HClO 1