In 1827, Robert Brown noticed pollen suspended in water bouncing around erratically. It wasn't until 1905 that Albert Einstein provided an acceptable explanation of the phenomenon (Kac 1947): Brownian motion is the random movement of particles (e.g., pollen) in a fluid (liquid or gas) as a result of collisions with atoms and molecules. Movement of…

British scientist John Dalton (1766-1844), French scientist Joseph Louis Gay-Lussac (1778-1850), and Italian scientist Amedeo Avogadro (1776-1856) are familiar to many chemistry students. Such students may understand the importance of Dalton's atomic theory, model how Gay-Lussac's law relates the pressure and the temperature of a gas, and use…

A series of interactive, instructional units have been developed that integrate computational molecular modelling and visualization to teach fundamental chemistry concepts and the relationship between the molecular and macro-scales. The units span the scale from atoms, small molecules to macromolecular systems, and introduce many of the concepts…

The results from a study to explore pre-service teachers' understanding of ionization energy, a topic that features in A-level (grade 11 and 12) chemistry courses. in Singapore , is described. A previous study using a two-tier multiple choice diagnostic test has shown that Singapore A-level students have considerable difficulty understanding the…

One of the more interesting areas of problem solving in chemistry attempts to answer the question, "What do students understand about the molecular level of chemistry?" This question is also implicit in the more traditional area of mathematical problem solving but in this paper, more focus is placed on devising ways to help students develop a…

Describes a science project in which students make models of polymers using polyvinyl alcohol solution. Students make T-shirts using polymer paint to remind them of their activities. (MDH)

Presents an activity in which models help students visualize both the DNA process and transcription. After constructing DNA, RNA messenger, and RNA transfer molecules; students model cells, protein synthesis, codons, and RNA movement. (MDH)

Chemistry can be described on three levels: sensory, molecular, and symbolic. Proposes a particle approach to teaching chemistry that uses magnets to aid students construct molecular models and solve particle problems. Includes examples of Johnstone's model of chemistry phenomena, a problem worksheet, and a student concept mastery sheet. (MDH)

This manual is part of a series of materials designed to reinforce essential concepts in physical science through interactive, language-sensitive, problem-solving exercises emphasizing cooperative learning. The manual is intended for limited-English-proficient (LEP) students in beginning physical science classes. The materials are for teams of two…