Describes an experiment (carried out in less than two hours) in which the merits of countercurrent extraction are immediately evident by visible colors. The experiment requires eight 125-ml separatory funnels, 250ml of 1-butanol, 250ml of 0.1-0.5 molar hydrochloric acid, and a small amount of Sheaffer's Skrip blue-black soluble ink. (JN)

Explains the physical principles which result in various colors of the sky. Topics addressed include: blueness, mystical properties of water vapor, ozone, fluctuation theory of scattering, variation of purity and brightness, and red sunsets and sunrises. (DH)

Proposes that colored compounds be classified by reference to a standard color-order system incorporating a color dictionary. Argues that the colors of new compounds could be incorporated into the characterization process and into computer storage systems. (TW)

Reasons for color in sedimentary rocks are explored. Graphs relating the color of rock and corresponding organic content and oxidation state of iron, and of the temporal evolution of a rock sample, are presented. The development of these graphs is discussed. (CW)

Describes construction and operation of an inexpensive and portable educational hallway exhibit on color mixing. (JRH)

Tested demonstrations on (a) color development through the formation of subtractive primary dyes and (b) fluidity of gases are presented. (CP)

The effect of background color on the perception of color by students is discussed. Explanations on why students only see certain colors when viewing colored marks on a blackboard through different color filters are provided. (KR)

Two different methods of measuring the temperature of an incandescent lamp at various voltage levels are described. By observing the color produced at a particular voltage levels, the lamp's color as a function of temperature can be determined. Needed equipment include a variac, a voltmeter, and an ammeter. (KR)

Presents several demonstrations in spectroscopy. (RH)

Describes experiments which focus on the perception of three dimensions. Discusses the cues about distance and depth and the role they have in perceptions of three dimensions. Evaluates the effect of color on the illusion on depth. (ML)

An approach which is designed to help students better understand the utility of models in understanding and doing physics, specifically in a course in light and color, is described in this paper. Explanations are given and illustrations are provided of an analogue model of waves which assist in the creation of an abstract model to deduce Snell's…

By considering colors as sets of wavelengths and using Boolean Algebra of sets, the effects of combining colors can be represented in a formal mathematical system. (SD)

Discusses children's ideas about colored objects and colored shadows, with special attention to the organization of these ideas into mental models. The clarification of these models provides instructional tools that serve to assess and confront students' naive conceptions. Subjects were visitors to a science museum who engaged in interactive…

This study focused on misconceptions related to light and vision. Researchers administered diagnostic tests about light, vision, and color before and after instruction to 227 fifth-grade students over a 2-year period. They also conducted 11 clinical interviews. The tests and interviews revealed that almost all students shared certain…

Explains a demonstration that shows the additive nature of light using three overhead projectors. (GA)