Reducing Agents For Metallurgy and Good Health

Richard Feynman (1919-1988), winner of the 1965 Nohel Prize in physics, was one of the most original thinkers of this century. He wrote, Scientific knowledge is a body of statements of varying degrees of certainty—some most unsure, some nearly sure, but wow absolutely certain. Now, we scientists are used to this, that it is possible to live and not know.  

Feynman gave the United States a lesson in how science works when he used a simple experiment to uncover the reason for the disastrous explosion of the space shuttle Challenger. On launch day, January 28, 1986, the weather was unusually cold in Florida—the temperature was 29°F. A few moments after launch, the world watched in horror as the shuttle and its rockets exploded in a gigantic fireball, killing all the astronauts aboard. 

A commission was appointed to investigate the cause of the explosion. It was Feynman who reasoned that due to the cold temperature, rubber O-rings used to seal joints in the solid-fuel booster rockets had not expanded properly. This failure allowed hot flames from the booster rocket to burn through the hydrogen fuel tank. The result was 

DEMONSTRATING THAT AN O-RING OF THE TYPE USED IN THE SPACE SHUTTLE CHALLENCER DOES NOT RETAIN ITS FLEXIBILITY WHEN COLD AND THUS WOULD ALLOW GASES TO ESCAPE FROM THE ROCKET. 

Chlorine itself is an oxidizing agent of vital importance in ensuring the purity of drinking water and water that is returned to natural waterways. Treatment of wastewater and drinking water is described in Sections 11.10 and 11.12. 

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