CH 101 Lecture Notes - Lecture 9: Transition Metal, Alkaline Earth Metal, Rare Earth Element

• School: University of Alabama
• Department: Chemistry
• Course: CH 101
• Professor: John Mc Duffie

Document Summary

When elements undergo chemical reactions, the reacting elements do not turn into other elements. This requires that all the atoms present when you start the reaction will still be there after the reaction. Because the number of protons determined the kind of element, the number of protons in the atom does not change in a chemical reaction. However, many reactions involve transferring electrons from one atom to another. When atoms gain or lose electrons, they acquire a charge. Charged atoms or groups of atoms are called ions. When atoms gain electrons, they become negatively charged ions, called anions. When atoms lose electrons, they become positively charged ions, called cations. For each negative charge, the ion has one more electron than the neutral atom. Anions are named by changing the end of the name to -ide. For each positive charge, the ion has one less electron than the neutral atom. Cations are named the same as the metal.