Atomic Symbols, Atomic Numbers, and Mass Numbers
By Debbie McClinton, Dr. Miriam Douglass, Dr. Martin McClinton
Learners read definitions of atomic symbols, atomic numbers, and mass numbers and then answer questions about the number of neutrons, protons, and electrons in select elements.
Learners read the definition of atomic weight and obtain the weights of elements by viewing the Periodic Table and charts that list atomic weights by name or symbol.
Balancing Oxidation-Reduction Equations
In this animated activity, learners examine the terms "half-reaction," "oxidizing agent," and "reducing agent" and follow five interactive examples to balance equations for oxidation-reduction reactions. Three problems are provided as a self-check.
Boiling Point of a Liquid
Learners examine how the boiling point increases with increasing pressure. An example from industry is given.
Calculating Formula Weight and Molecular Weight
In this interactive object, learners calculate formula and molecular weights by working through five examples and two problems.
Calculating Formula Weight and Molecular Weight
Calculation of Atomic Weight from Isotopic Composition
Learners examine the method for calculating the atomic weight of copper from the natural percent composition of each of its two isotopes.
By Debbie McClinton, Dr. Martin McClinton
Students read an explanation of chemical formulas in this animated activity. A quiz completes the object.
Common Types of Oxidation-Reduction Reactions
Learners identify combination, decomposition, displacement, and combustion types of redox reactions. They also watch a video clip that demonstrates the reaction of sodium and water.
Common Types of Oxidation-Reduction Reactions (Screencast)
Determining Empirical and Molecular Formulas
Learners follow a four-step process to determine the empirical formula of a compound from the masses of its constituent elements. The molecular formula is determined in a fifth step using the molecular weight of the compound.
Determining Empirical and Molecular Formulas (Screencast)
In this animated and interactive object, learners examine the inverse proportionality of wavelength and frequency and their relationship to the speed of light.
Electromagnetic Radiation (Screencast)
Heat of Fusion and Heat of Vaporization
Learners examine graphs and read that the heat of fusion is the heat energy absorbed by one mole of solid as it is converted to liquid, while the heat of vaporization is the heat energy absorbed by one mole of liquid as it is converted to gas.
In this well-illustrated activity, learners examine the three types of intermolecular forces: dipole-dipole forces, London or Van der Waals forces, and the hydrogen bond. Two interactive questions are included.
Ions are electrically charged particles obtained from an atom or from a chemically bonded group of atoms by adding or removing electrons. Eight examples illustrate the number of protons, neutrons, and electrons in positive ions (cations) and in negative ions (anions).
The definition of an isotope is illustrated using the three isotopes of carbon. The three isotopes of hydrogen are discussed as exceptions.
Melting Point and Freezing Point
Learners observe that the melting of a solid and the freezing of its liquid occur at the same temperature. The melting point is an intrinsic property and is used to identify a substance.
Mole Ratios in Chemical Equations
Learners use the coefficients in a balanced equation to develop the mole ratios of reactants and products involved in the reaction. Five interactive examples illustrate the method, and students test their knowledge by working four problems.
Naming Binary Ionic Compounds Containing Fixed Oxidation State Cations
Learners examine a table containing the names of common cations and anions. They then check their knowledge by answering a series of questions.
Learners examine a table containing the names of common cations and anions.
Naming Binary Ionic Compounds Containing Variable Oxidation State Cations
Roman numerals are used to identify the charges on metal cations having multiple oxidation states. Five examples are provided for practice.
Naming Binary Ionic Compounds Containing Variable Oxidation State Cations (Screencast)
Naming Compounds Containing Polyatomic Ions
Learners examine a table of common polyatomic ions. Eight examples are provided for practice.
Learners assign oxidation numbers to atoms in neutral compounds and in polyatomic ions. Six examples are worked through in detail, and three problems are provided.
Oxidation States of Ions
Learners examine the periodic table to identify metallic elements that have either fixed or variable oxidation states.
Learners examine the meaning of oxidation, reduction, and half-reaction, and watch a film showing the deposition of copper metal from the reduction of copper (II) ion by aluminum. A brief quiz completes the activity.
Percent Composition of Compounds
Learners examine the method used to calculate the mass percent of an element in a compound. Three examples and one problem illustrate the method.
Percent Composition of Compounds (Screencast)
Learners examine phase diagrams that show the phases of solid, liquid, and gas as well as the triple point and critical point.
Learners examine how melting, vaporization, and sublimation require energy input while freezing and condensation release energy.
Product Yields in Chemical Reactions
Learners examine the meaning of theoretical yield, actual yield, and percent yield. They test their knowledge by solving two problems.
Product Yields in Chemical Reactions (Screencast)
The Effect of Temperature on the Vapor Pressure of a Liquid
Learners examine how vapor pressure is calculated. The vapor pressure of a liquid increases with increasing temperature. If the heat of vaporization and the vapor pressure at one temperature are known, the vapor pressure at a second temperature can be calculated.
The Limiting Reagent in Chemical Reactions
In this interactive object, learners determine the limiting reagent and the excess reagent in chemical reactions. Learners test their knowledge by solving three problems.
The Mole and Avogadro's Number
Learners examine how chemists use moles to "count" atoms by weight. Examples are given.
The Solid State
In this well-illustrated object, learners examine the structures and properties of the four types of solids: molecular, metallic, ionic, and covalent network. Five interactive questions are provided.
Types of Elements in the Periodic Table and Their Properties
Students review the positions of metals, metalloids, and nonmetals in the Periodic Table and the general characteristics of each. A quiz completes the object.
Types of Elements in the Periodic Table and Their Properties (Screencast)
In this screencast, we review the positions of metals, metalloids, and nonmetals in the Periodic Table and the general characteristics of each.
Vapor pressure is the pressure exerted by molecules in the gas phase in equilibrium with a liquid or a solid. Two examples are used to illustrate vapor pressure: the drying of clothes and the evaporation of ice.