Dating uses properties atoms
Dating uses properties atoms - dating websites for kids 12 14
(See sidebar on Davy in the calcium entry in Volume 1.) There are very few uses for potassium as a pure element.However, compounds of potassium have many important applications, the most important of which is as a fertilizer.
Davy used a new method of isolating elements that he had invented, electrolysis.
The alkali metals are the elements that make up Group 1 (IA) of the periodic table.
The periodic table is a chart that shows how chemical elements are related to one another.
Early humans also knew about a similar substance called mineral alkali. The modern chemical name for soda ash is sodium carbonate (Na ).
This material was made from certain kinds of rocks. For many centuries, people had trouble telling "vegetable alkali" and "mineral alkali" apart.
By the late 1700s, chemists were reasonably sure that both potash and soda ash contained elements they had never seen.
They tried to think of ways to break these compounds down into their elements.Early humans were familiar with potash, a potassium compound that forms when wood burns. That name comes from the origin of the material ("vegetable" plants that contain wood) and the most important property of the material, alkali.Wood ashes were washed with water to dissolve the potash. The word alkali means a strong, harsh chemical that can be used for cleaning.Davy named these two elements after their much older names: potassium for "potash" and sodium for "soda ash." Potassium is a soft, silvery-white metal with a melting point of 63°C (145°F) and a boiling point of 770°C (1,420°F).Its density is 0.862 grams per cubic centimeter, less than that of water (1.00 grams per cubic centimeter).Then Davy thought of another way to separate potash and soda ash into their elements. Instead, he melted a sample of potash and a sample of soda ash.