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.
Students read about the basic organization and structure of the periodic table of elements. By clicking on the symbol, they can read that element's atomic number and weight. In an exercise, students identify elements as belonging to a group, a period, or neither.
The Formation of Ester Bonds in the Synthesis of Lipids
In this animated object, learners examine the formation of ester bonds in the synthesis of lipids using triglyceride biosynthesis as an example. Ester bond formation is described as a dehydration synthesis reaction.
Learners view several movie clips that demonstrate the use of an indicator to follow the neutralization reaction that occurs when an acid and a base are mixed. Students test their knowledge in a series of questions. Immediate feedback is given.
In this animated and interactive object, learners examine kinetic and potential energy as well as the first law of thermodynamics and the flow of energy between a system and its surroundings. Students also answer questions about exothermic and endothermic reactions
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.
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.
In this animated and interactive object, learners observe how two, three, or four groups of electrons around the central atom cause the shape of the molecule to be linear, trigonal planar, bent, tetrahedral, or pyramidal. Seven examples and eight interactive questions are provided.