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Regents Chemistry. Chemical Nomenclature Ionic Compounds Binary Type I Binary Type II Polyatomic Nomenclature Covalent Compounds. Naming Compounds. Common names were originally developed to name compounds Ex: Epsom salts, milk of magnesia, gypsum and laughing gas
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Regents Chemistry • Chemical Nomenclature • Ionic Compounds • Binary Type I • Binary Type II • Polyatomic Nomenclature • Covalent Compounds
Naming Compounds • Common names were originally developed to name compounds • Ex: Epsom salts, milk of magnesia, gypsum and laughing gas • Too many common names..a system had to be developed!
Naming Compounds • Binary compounds – compounds that are composed of two elements • We will examine two classes of binary compounds • 1. Compounds that contain a metal and a nonmetal • 2. Compounds that contain two nonmetals
Naming Binary Ionic Compounds • Binary ionic compounds result when a metal combines with a nonmetal • The metal loses electrons as the nonmetal gains electrons • The result is a positive cation (the metal) and a negative anion (the nonmetal) • In naming ionic compounds, we simply name the ions
Naming Binary Ionic Compounds • We will learn how to name two types of ionic compounds (polyatomic ion naming will come later) • Type I compounds – The metal is present in only one type of cation - look at periodic table! • Ex: Na+, K+, Ca2+, Al3+ • Type II compounds – The metal present can form two (or more) cations that have different charges - look at periodic table! • Ex: Cr2+, Cr3+, Cu+, Cu2+
Naming Rules for Type I Ionic • 1. The cation is always named first and the anion second • 2. A simple cation (obtained from a single atom) takes its name from the name of the element. • Ex: Na+ Sodium ion • 3. A simple anion (obtained from a single atom) is named by taking the first part of the elemental name and adding – ide • Ex: F- Fluoride ion
Examples • Name the following compounds NaCl sodium chloride KI potassium iodide CaS calcium sulfide
Examples • Write the chemical formula for the following: Barium Fluoride BaF2 Potassium Sulfide K2S Aluminum Oxide Al2O3 Lithium Phosphide Li3P Strontium Nitride Sr3N2 STOP
Regents Chemistry • Naming Type II Compounds
Naming Type II compounds • Type II compounds – The metal present can form two (or more) cations that have different charges - look at periodic table! • Ex: Cr2+, Cr3+, Cu+, Cu2+ • We cannot only look at the periodic table to determine the charge…we must determine the charge according to the chemical formula
Determing the correct charge • All compounds must be electrically neutral..so • we use the charge of the anion to determine the charge of the cation…and multiply the charges by the number of atoms to determine the overall net charge
Example CuCl Cl comes in as Cl- : -1 x 1 Cl ion = -1 Cu must come in as a +1 :+1 x 1 Cu ion = +1 -1 + +1 = 0 , the charges balance Copper (I) Chloride
Naming Type II Rules • Use the same system of naming as Type I binary compounds..except • add the following after the cation depending on the cation’s charge (I) +1 (V) +5 (II) +2 (VI) +6 (III) +3 (VII) +7 (IV) +4
Practice HgO Mercury (II) Oxide Fe2O3 Iron (III) Oxide Lithium Phosphide Li3P Ca3N2 Calcium Nitride Worksheet
Regents Chemistry • Polyatomic Ion Compound Nomenclature
What’s a polyatomic ion? • A polyatomic ion consists of two or more elements bonded together that posess an overall net charge that can be used to form an ionic bond with a metal cation • We looked at some of these! SO42-
Polyatomic Ion Intro… • Polyatomic ions have specific names… • You must be able to recognize polyatomic ions in chemical formulas and chemical names • You reference tables can help! • See the table on the front page
Naming Polyatomic Ions… • Some polyatomic ions have general names that are made from modification of the names of the elements involved • Ex: NH4+ Ammonium Ion CN- Cyanide Ion
Naming Oxyanions • Oxyanions are polyatomic ions (anions) that contain atoms of an element and different numbers of oxygen atoms • When there are two members in such a series, the anion with the lesser number of oxygen is given the ending –ite and the larger number ends in –ate Sulfite Ion SO42- Sulfate Ion SO32-
Naming Oxyanions cont… • If there are more that two in the series, we use the prefix hypo for the member with the fewest oxygen and per for the one with the most oxygen ClO-hypochlorite ion ClO2- chlorite ion ClO3- chlorate ion ClO4-perchlorate ion
Naming Compounds that Contain Polyatomic Ions… • We use the cation name and roman numerals (if needed) and the polyatomic ion’s name • Ex: Na2SO4 2 x Na+ sodium sulfate 1 x SO42-
Examples iron (III) nitrate Fe(NO3)3 manganese (II) hydroxide Mn(OH)2 copper (II) sulfate CuSO4
Regents Chemistry • Naming Type III Binary Compounds Non-metal to non-metal
Type III Binary Compounds • Type III Binary Compounds - are compounds that contain only nonmetals participating in covalent bonds (sharing of electrons)
Rules for Naming Type III • 1. The first element in the formula is named first, and the full element name is used • 2. The second element is named as though it were an anion (-ide ending) • 3. Prefixes are used to denote the numbers of atoms present. • 4. The prefix mono is never used for naming the first element
Prefixes for Naming Type III PREFIX NUMBER INDICATED mono- 1 di- 2 tri- 3 tetra- 4 penta- 5 hexa- 6 hepta- 7 octa- 8
Practice • BF3 • NO • N2O5 • carbon tetrachloride boron trifluoride nitrogen monoxide dinitrogen pentoxide CCl4 worksheet
Regents Chemistry • Revisiting the Periodic Table • Trends and Families of the Table
Properties of Elements • Trends to be familiar with: • Ionization Energy • Atomic Radii • Ionic Radii • Electronegativity • Reactivity of Elements
Summary of Trends • Ionization Energy – increases from left to right and up the columns • Atomic Radii – increases from right to left and down columns • Ionic Radii – depends on if the atom looses or gains electrons • Electronegativity – increases from left to right and up the columns • Reactivity – Groups 1,2 and 17 along with oxygen are most reactive
Families on the Table • 3 – day website project: see handout