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While most chemical reactions take place almost immediately, there are some which can be made to occur after a timed delay. These are the so-called clock reactions. By varying the temperature or concentration of reactants, the delay can be shortened or lengthened in a striking manner.
The progress of sciences such as chemistry is due to the work of many great men. These men have made their mark in science by their curiosity and their efforts to understand natural laws. Some of these men and the fields in which they worked are: Sir Robert Boyle, properties of gases; Sir Isaac Newton, laws of motion; Antoine Lavoisier, analytical chemistry; Sir J. J. Thomson, discoverer of the electron; Jacobus von't Hoff, physical chemistry.
Changes in nature are classed as either physical or chemical changes. Examples of both types of changes are shown. Simple chemical reactions such as the burning of magnesium and phosphorous are demonstrated. Other, more complicated reactions include those of the decomposition and double displacement type.
The tale of the foolish little chicken who is hit on the head by an acorn and thinks the world is falling in is told by Poindexter and his friends. How "Chicken Little" nearly starts a panic among the animals until a sensible friend stops them is the story for today.
A public service announcement from the Citizens for Clean Air in which the close-up and audio of a man breathing overlays shots of cars, planes, factory chimneys, and other sources of air pollution. An offscreen male narrator describes the many kinds of pollutants in the air we breathe and urges the viewer to write to the organization's address. Submitted for the Clio Awards.
Presents a high-school class studying god citizenship in the community and in the school. Dramatizes the manner in which the student committees organized projects for improving school elections, choosing proper representatives for student government, welcoming new students, and up-grading lunch room conditions. Emphasizes that good citizenship in the school produces good citizenship in the community.
In this program, film sequences illustrate the steps in the prison separation and analysis technique, and an inmate tells of his experience with the classification system. Criminologist Joseph D. Lohman outlines the basic and conflicting ideas which underlie imprisonment, punishment and rehabilitation. Powers and Lohman
emphasize the need for professional personnel to implement the classification of prisoners and the importance of setting up programs to meet their individual needs.
Brushy, Susie-Q and Linda leave so much litter when they play in the park that the clean-up man has to stay late to tidy up after them. When the children realize that they are keeping him from a party, they correct their mistake and help clean up.
Clever Elsie really isn't very clever at all. Marionettes tell the story of Clever Elsie who sweeps with the broom upside down to keep from wearing out the straw. One day, Clever Elsie goes to the cellar to get some cider and she notices a pick-ax stuck in a beam. She begins to think that if she should ever marry and have a child and send him to the cellar for cider, the pick-ax might fall on his head and kill him and Elsie begins to cry. Her parents come to the cellar with Hans, who is looking for a clever wife, and Elsie tells them her story. Soon everyone is crying and Hans decides to marry Elsie because she is so clever.
