In this interactive lesson, learners study examples of nouns that can be counted and nouns that cannot. They then identify whether a word is a "count" or a "noncount" noun in a practice exercise.
In this animated activity, learners read about the properties of a square and its components. They then work practice problems to find the perimeter and area of squares.
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.
In this interactive learning object, the learner practices sizing a tank-type water heater for one- and two-family residences, townhouses, and apartments with individual water heaters.
Users of this learning object evaluate the early online experiences of four hypothetical students and record the lessons that can be learned about what to do and what not to do to create effective online learning environments.
Introduction to Safety in the Chemistry Lab (Video)
Learners read about lab equipment and basic safety measures. In a quiz, they view photos and determine if the lab technicians pictured are using safe practices.