Unit Conversions
By Jill Larson
In this animated and interactive object, learners follow two rules to write unit conversion fractions.
The Effect of Temperature on the Vapor Pressure of a Liquid
By Debbie McClinton, Dr. Miriam Douglass, Dr. Martin McClinton
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.
Boiling Point of a Liquid
Learners examine how the boiling point increases with increasing pressure. An example from industry is given.
The Three States of Matter
By Dr. Miriam Douglass, Dr. Martin McClinton
In this animated and interactive object, learners examine the properties of liquids, solids, and gases.
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.
Precipitation Reactions
In this interactive and animated object, learners use solubility rules to predict when an insoluble ionic compound will precipitate in a double replacement reaction. Four step-by-step examples are given.
Atomic Symbols, Atomic Numbers, and Mass Numbers
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.
Gas Volume vs. Temperature (Charles's Law)
In this animated object, learners examine how gas volume varies directly with absolute temperature (K at constant pressure). An example of a sample of gas at two conditions of volume and temperature is used to illustrate the law.
Equilibrium
In this animated object, students examine the role equilibrium plays in everyday life. Formulas are presented in an interactive way.
Oxidation Numbers
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.
Macroscale vs. Nanoscale
By Karen Nordell
In this colorful, interactive object, learners examine how materials on the nanoscale compare with those on the macroscale. The focus is on the difference between macroscale and nanoscale gold in both color and melting point.
How Pressure Changes Boiling Temperature
By Terry Bartelt, Terry Fleischman
Learners study the effect that pressure has on boiling temperatures. Once a liquid has reached a full boil, additional heat does not raise the liquid’s temperature; however, pressure can vary the boiling point of a liquid. A brief quiz completes the activity.
Atomic Weight
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.
Introduction to the Periodic Table (Screencast)
By Mona Wenrich
In this screencast, students read about the basic organization and structure of the periodic table of elements. Students identify elements as belonging to a group, a period, or neither.
Lewis Dot Structures of Covalent Compounds
In this interactive and animated object, students distribute the valence electrons in simple covalent molecules with one central atom. Six rules are followed to show the bonding and nonbonding electrons in Lewis dot structures. The process is well illustrated with eight worked examples and two interactive practice problems.
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.
Absolute Zero Temperature
Learners view illustrations showing the direct dependence of the volume of a gas on temperature and consider the relationship between the Kelvin and Celsius temperature scales.
Conversion Between Mass and Moles of an Element (Screencast)
Atomic weights are used to convert the mass of a sample into the number of moles of the element in the sample and vice versa. Four examples are provided for practice.
A Biological Example of Water Solubility
In this animated object, students examine the role that the solubility of water plays in various biological functions.
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.
Chemistry Math - Solving a Formula (Screencast)
By Laurel Maney
Students use algebra to rearrange formulas and solve for the missing volume, density, or mass quantity.
Pressure and Boyle's Law
Students examine standard pressure in this interactive object.
Ions
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).
Controlling pH
By Terry Bartelt
Learners view an animated presentation showing how the pH level of a cleaning solution is controlled in a closed-loop system in a manufacturing setting. A quiz completes the activity.
Standard Molar Volume
By Dr. Miriam Douglass
Learners observe that the volume of one mole of any gas is 22.4 L at standard temperature and pressure. An illustration shows that only the mass of the molar volume differs with the identity of the gas.