900 likes | 1.06k Views
NAMING AND WRITING FORMULAS FOR COMPOUNDS. OUTLINE. IUPAC BOHR DIAGRAMS FOR ATOMS TYPES OF CHEMICAL BONDS MOLECULAR COMPOUNDS TYPES SIMPLE COVALENT COMMON NAME IONIC COMPOUNDS SIMPLE IONIC MULTIVALENT POLYATOMIC/COMPLEX HYDRATED IONIC ACIDS. IUPAC.
E N D
OUTLINE • IUPAC • BOHR DIAGRAMS FOR ATOMS • TYPES OF CHEMICAL BONDS • MOLECULAR COMPOUNDS • TYPES • SIMPLE COVALENT • COMMON NAME • IONIC COMPOUNDS • SIMPLE IONIC • MULTIVALENT • POLYATOMIC/COMPLEX • HYDRATED IONIC • ACIDS
IUPAC • International Union of Pure and Applied Chemists • A global organization that sets the standards in chemistry. • One job of the IUPAC is to give compounds SYSTEMIC NAMES.
BOHR DIAGRAMS FOR ATOMS • AKA:ENERGY LEVEL DIAGRAMS • These are a way of drawing atoms in a 2-D manner. • Keep in mind that atoms are actually 3-D, and there are more complex representations of atoms. • Bohr models show the NUCLEUS and the ELECTRON ENERGY LEVELS of an atom.
BOHR DIAGRAMS . . . • 3 types of SUBATOMIC PARTICLES • PROTONS (p+) • Positively charged particles – large mass • Atomic Number = Number of Protons • ELECTRONS (e-) • Negatively charged particles – very small mass • Number of Electrons = Number of Protons • NEUTRONS (no) • Neutral particles – large mass • Number of neutrons = Atomic Mass – Atomic Number
BOHR DIAGRAMS . . . • NUCLEUS • center of the atom • contains p+ and n0 • atomic mass is concentrated here • ELECTRON ENERGY LEVELS • areas around the nucleus where electrons may be found • 3 LEVELS: • FIRST LEVEL (Closest to Nucleus) maximum of 2 e- • SECOND LEVEL maximum of 8e- • THIRD LEVEL maximum of 8e-
BOHR DIAGRAMS . . . • EXAMPLE: DRAW BOHR DIAGRAMS FOR: • Li – lithium atom • ATOMIC # = _____________ • ATOMIC MASS = _____________ • # p+ = ________________________ • # e- = ________________________ • # no = ________________________
BOHR DIAGRAMS . . . • EXAMPLE: DRAW BOHR DIAGRAMS FOR: • Ne – neon atom • ATOMIC # = _____________ • ATOMIC MASS = _____________ • # p+ = ________________________ • # e- = ________________________ • # no = ________________________
BOHR DIAGRAMS . . . • EXAMPLE: DRAW BOHR DIAGRAMS FOR: • S – sulfur atom • ATOMIC # = _____________ • ATOMIC MASS = _____________ • # p+ = ________________________ • # e- = ________________________ • # no = ________________________
HOMEWORK!!! • Do Bohr diagrams for the first 18 elements. • Be sure to: • Write in the atomic number and mass number. • Write the name of the atom. • Show p+ and n0 in the nucleus • Draw electrons in the energy levels.
BOHR DIAGRAMS . . . • VALENCE LEVEL • The outermost energy level • Electrons in this level are VALENCE ELECTRONS • Atoms with FULL valence shells are STABLE, meaning they do not normally react with other atoms. Which Group??? • Atoms that do not have full electron energy levels are unstable and must GAIN, LOSE, or SHARE electrons to become stable.
CHEMICAL BONDS • A chemical bond is a force of attraction between atoms. • 2 TYPES of Chemical bonds • COVALENT BONDS • AKA: molecular bonds • “co” – together/sharing , “valent” – outer shell • Occur when 2 nonmetalsshare at least 1 pair of electrons • Molecules with covalent bonds are NON-ELECTROLYTES. ie. their solutions DO NOT CONDUCT electric current
CHEMICAL BONDS • IONIC BOND • Occur between a metal and a nonmetal • Metals lose electrons to form CATIONS (+) • Nonmetals gain electrons to form ANIONS (-) • Ionic compounds are ELECTROLYTES. • ie. their solutions CONDUCT electric current
MOLECULAR COMPOUNDS • Form when 2 or more NONMETALS share electrons in COVALENT BONDS. • 2 TYPES: • BINARY Molecular Compounds • TRIVIAL NAME Molecular Compounds
BINARY MOLECULAR COMPOUNDS • Use these IUPAC prefixes:
Write name from formula • Write NAMES of elements, with the 2nd element ending in “-ide”. • Use PREFIXES to indicate the number of each atom. • Do NOT use the prefix “mono” for the 1st element. DO use “mono” with the 2nd element.
Write name from formula • N2O4 ________________________ • P2O5 ________________________ • CCl4 ________________________ • S2H2 ________________________ • CO________________________
Write formula from name • Write ELEMENT SYMBOLS for each element in the compound. • Use each PREFIX to write the number of each atom as a SUBSCRIPT next to the symbol (omit the subscript 1).
Given Name, Write Formula EXAMPLE • carbon monoxide ____________ • triphosphorus pentabromide ____________ • sulfur hexafluoride ____________ • dicarbon tetrahydride ____________
TRIVIAL Molecular Compounds AKA: COMMON NAME molecular compounds. • These must be memorized.
HOMEWORK ALERT!!! • Complete the NEXT THREE SHEETS in your handout for HOMEWORK. • Refer to the following notes for help: • FIRST SHEET • Given Name, Write Formula Notes • SECOND SHEET • Given Formula, Write Name Notes • THIRD SHEET • Everything! • Watch out for those common name molecular compounds!!!
IONIC COMPOUNDS • Atoms that are not NOBLE GASES will GAIN, LOSE, or SHARE ELECTRONS to become more stable. • SHARING electrons results in a COVALENT BOND and a MOLECULAR COMPOUND. • When an atom loses or gains electrons it forms an ion. • A ionic bond is a force of attraction between positive and negative ions. • OCTET RULE • Atoms that have an octet of valence electrons are STABLE and UNREACTIVE.
Cations - POSITIVE ions that are formed from a LOSS of electrons. + • Cations have more PROTONS than ELECTRONS and therefore has a net POSITIVE charge. • - METALS form cations.
e g a t i v e r e anions • - NEGATIVE ions that are formed from a GAIN of electrons. • Anions have more ELECTRONS than PROTONS and therefore has a net NEGATIVE charge. • - NONMETALS form anions. Electron Blues
BOHR DIAGRAMS FOR IONS • METALS • ATOMS of METALS will LOSE electrons to become CATIONS. • ATOMS with 1, 2, or 3 VALENCE electrons will LOSE these electrons to form 1+, 2+, or 3+ ions respectively. • GROUP 1 ATOMS – ALKALI • 1valence electrons(s) (will lose 1 to become stable) • 1 + ion • GROUP 2 ATOMS – ALKALINE EARTH • 2valence electrons(s) (will lose 2 to become stable) • 2 + ion • GROUP 13 ATOMS • 3valence electrons(s) (will lose 3 to become stable) • 3 + ion
BOHR DIAGRAMS FOR IONS • NONMETALS • ATOMS of NONMETALS will GAIN electrons to become ANIONS. • ATOMS with 5,6, or 7 VALENCE electrons will GAIN these electrons to form 3-, 2-, or 1- ions respectively. • GROUP 15 ATOMS • 5valence electrons(s) (will gain 3 to become stable) • 3 - ion • GROUP 16 ATOMS • 6valence electrons(s) (will gain 2 to become stable) • 2 - ion • GROUP 17 ATOMS - HALOGENS • 7valence electrons(s) (will gain 1 to become stable) • 1 - ion • GROUP 18 ATOMS - NOBLE GASES • FULL outer valence levels
IONIC COMPOUNDS • Made from a METAL and a NONMETAL • Metals form CATIONS • Nonmetals form ANIONS • An IONIC BOND is the force of attraction between cations and anions (opposite charges attract) • Ions are arranged in a CRYSTAL LATTICE.
IONIC COMPOUNDS eg. NaCl crystal lattice
IONIC COMPOUNDS Each cations is surrounded by 6 anions and vice versa • eg. NaCl Cl- Cl- Cl- Cl- Cl- Cl- Cl- Cl- Cl- Cl- Cl- Cl- Cl- Cl- Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Na+ Cl- Cl- See Figure 4, p. 189
1. SIMPLE BINARY IONIC COMPOUNDS • two types of ion (a cation and an anion) • cations only have ONE possible charge WRITE THE NAME FROM THE FORMULA • Write the name of the CATION before the ANION (Be positive before being negative • Change the ANION suffix to “-ide” Do NOT use CAPITALS Do NOT use PREFIXES
1. SIMPLE BINARY IONIC COMPOUNDS MgBr2 _____________________________ KCl _______________________________ Na2S _____________________________ Mg3P2 _____________________________ Ba3N2 ______________________________ • What’s wrong with these for BaS? barium sulfur Barium Sulfide barium sulfuride
HOMEWORK! • Do the following sheet in the booklet for homework: • Follow rules for: • “GIVEN FORMULA, WRITE NAME” for Ionic Compounds.
1. SIMPLE BINARY IONIC COMPOUNDS WRITE THE FORMULA FROM THE NAME 1. Determine each ION CHARGE from the periodic table. 2. Use the “crossover” method to write the formula for the compound. • The overall charge on a compound is “zero”. • Ion ratios must be reduced to lowest terms.
1. SIMPLE BINARY IONIC COMPOUNDS EXAMPLE: • sodium bromide _____________________ • barium iodide ___________________
SIMPLE IONIC COMPOUNDS EXAMPLE: • magnesium oxide _____________________ • aluminum oxide ___________________
HOMEWORK!!! • Do the next two sheets for homework! • FIRST PAGE: • Given NAME, Write FORMULA • SECOND PAGE: • TOP HALF – Molecular Compound Naming • BOTTOM HALF – Ionic Compound Naming