Chemistry Naming Compounds and Writing Formulas

Page 1: Chemical Names and Formulas Overview

  • Overview of essential concepts in chemical nomenclature.

    • Metals and Non-Metals: Distinction between these categories.

    • Ions and Ionic Charges: Importance of understanding ion characteristics.

    • Types of Compounds: Differentiating between ionic and molecular compounds.

    • Systematic Names: Guidelines for writing names and formulas of compounds.

Page 2: Ions

  • Ions: Charged atoms that form through electron loss or gain.

    • Cations: Positively charged ions (e.g., Na+).

    • Anions: Negatively charged ions (e.g., Cl-).

Page 3: Ionic Charges (Groups 1-3)

  • Ionic Charges: Charge patterns in groups of the periodic table.

    • Group 1: +1 charge

    • Group 2: +2 charge

    • Group 13: +3 charge

Page 4: Ionic Charges (Groups 14-17)

  • Continued Ionic Charges:

    • Group 14: +4 or -4 charge

    • Group 15: -3 charge

    • Group 16: -2 charge

    • Group 17: -1 charge

Page 5: Chemical Formulas

  • Definition of Chemical Formula: Representation showing the kind and number of atoms in the smallest unit of a substance (e.g., NaCl).

Page 6: Ionic Compounds

  • Formula Units: The lowest whole number ratio of ions in an ionic compound.

    • Example: Na2Cl2 simplifies to NaCl.

    • Important note: There is no distinct molecule of NaCl due to its ionic nature.

Page 7: Writing Ionic Formulas

  • Balancing Charges: For ionic compounds:

    • If charges cancel: Write symbols directly (e.g., Na+ Cl- = NaCl).

    • If charges do not cancel, use criss-cross method for subscripts (e.g., Ca+2 Cl- = CaCl2).

    • Avoid moving the charge; only the number is transferred, omit writing the 1.

Page 8: Naming Compounds

  • Compound Classification: Understanding whether compounds are ionic or molecular is key to naming and writing formulas.

Page 9: Binary Ionic Compounds

  • Definition of Binary: Involves 2 elements.

  • Definition of Ionic: Involves a metal (cation) and a non-metal (anion).

  • Writing Formulas: Ensure charges balance for a neutral compound.

Page 10: Writing Formulas from Names

  • Name Structure:

    • 1st word = Cation (metal).

    • 2nd word = Anion (non-metal) with an "ide" ending.

Page 11: Examples of Binary Ionic Compounds

  • NaBr: Sodium Bromide

  • MgF2: Magnesium Fluoride

Page 12: More Example Binary Ionic Compounds

  • KCl: Potassium Chloride

  • Al2O3: Aluminum Oxide

  • Note: Anionic compound names end with "ide!"

Page 13: Naming with Transition Metals

  • Cation and Anion Structure:

    • Recognize the charge from the Roman numeral.

    • Silver (Ag): Notable exception with a +1 charge.

Page 14: Naming Transition Metals

  • Copper Example:

    • Copper (I) as Cu+ and forms compounds with Oxides.

    • Example: Cu2O.

Page 15: Writing Formulas with Transition Metals

  • Examples:

    • FeCl3: Iron (III) Chloride (Fe+3 Cl- 1).

    • FeCl2: Iron (II) Chloride (Fe+2 Cl- 1).

    • Emphasizes the necessity of utilizing the back crisscross method with Roman numerals for charge identification.

Page 16: Polyatomic Ions

  • Definition: Charged entities composed of tightly bound atoms that behave as a unit.

  • Examples: SO3^2-, NO2^-, ClO2^-

Page 17: Ternary Ionic Compounds

  • Definition: Comprised of three different elements, often containing polyatomic ions.

  • Characteristics: Retains cation and anion structure.

Page 18: Ternary Ionic Formulas

  • Example:

    • CaCO3: Combines Ca2+ with CO3^2-.

    • When charges cancel, symbols are written directly.

Page 19: Ternary Ionic Compounds: Naming

  • Calcium Nitrate:

    • For Ca(NO3)2, recognize that charges crisscross since they don’t cancel out directly.

Page 20: Types of Compounds

  • Molecular Compounds:

    • Comprised of molecules sharing electrons, usually made of two nonmetals.

    • Characteristics of bonding and attachment.

Page 21: Molecular Formula

  • Definition: Shows the number and types of atoms in a molecule of a compound.

  • Example: CO (Carbon Monoxide).

Page 22: Molecular Compounds Examples

  • Example Compounds: CS2, SiO2, BF3

    • Focus on composition of two nonmetals.

Page 23: Binary Molecular Compounds

  • Definition:

    • Consists of two elements (non-metals), emphasizing the absence of ionic charges.

Page 24: Naming Binary Molecular Compounds

  • Prefixes Usage: Indicates the number of atoms in each molecule.

Page 25: Covalent Prefixes

  • List of Covalent Prefixes:

    • Mono (1), Di (2), Tri (3), Tetra (4), Penta (5), Hexa (6), Hepta (7), Octa (8), Nona (9), Deca (10).

Page 26: Writing Binary Molecular Compounds

  • Example Calculation: CO2 - Carbon Dioxide;

    • Note that "mono" prefix is not used for the first element.

Page 27: Naming Binary Molecular Compounds

  • Methods:

    • Use prefix + element name (e.g., N2O = Dinitrogen Monoxide).

Page 28: Further Naming Methodology

  • Ending with Ide:

    • Utilize prefix + element root + ide for naming (e.g., PCl3 = Phosphorus Trichloride).

    • Reminder: All binary compounds conclude with "ide"!