107Stories About ChemistryINDEX |
102.
A Little Analogy, or How Chemists Fed Potassium to Plants
... There was a time when uranium, which is very well known now, dwelt in the back lanes of chemical science. Only glass staining and photography laid timid claims to it Then radium was found in uranium. Thousands of tons of uranium ores yielded an insignificant speck of the silvery metal but the wastes containing immense quantities of uranium continued to block up storage sites for a long time. However, uranium's hour struck at last when it proved to be the key to man's power over atomic energy. The wastes became a treasure. ... The Stassfurt salt deposits in Germany have been known since ancient times. They contained many salts, chiefly those of potassium and sodium. The sodium salt, which is table salt, immediately found usage. The potassium salts were discarded without regret and great mountains of them grew up around the mines. Nobody knew what to do with them. Though agriculture was in dire need of potassium fertilizers, the Stassfurt wastes could not be used because they contained a great deal of magnesium. Though beneficient to plants in small doses, magnesium is fatal in large amounts. Again chemistry came to the rescue. A simple method was found for removing the magnesium from the potassium salts and the mountains around the Stassfurt mines began to disappear like snow in spring. Science historians report that the first plant for treating potassium salts was built in Germany in 1811. A year later there were already four of them and by 1872 thirty-three German plants were processing more than half a million tons of the impure salt yearly. Potassium fertilizer plants sprang up shortly in many countries. Today the production of potassium salts in many countries exceeds their table salt output by many times. |