Alkali Metals
Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Caesium (Cs), and Francium(Fr)
The name "alkali" derives from an old word meaning "ashes of burned plants". Alkali metals are all shiny, soft and highly reactive. They all have a charge of +1 and can neutralize acids. A common alkali is sodium hydroxide (NaOH); it is formed when sodium oxide (Na2O) reacts with water.
The name "alkali" derives from an old word meaning "ashes of burned plants". Alkali metals are all shiny, soft and highly reactive. They all have a charge of +1 and can neutralize acids. A common alkali is sodium hydroxide (NaOH); it is formed when sodium oxide (Na2O) reacts with water.
Alkaline Earth Metals
Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), and Radium (Ra)
Alkaline earth metals are harder and less reactive than alkali metals. In the middle ages "earth" was any solid substance that did not melt and was not changed by fire into some other substance. Because many alkaline earth compounds have high melting temperatures and the same general appearance. These high temperatures were not attainable by those people, hence, the name "earth" was applied and stuck till today.
Alkaline earth metals are harder and less reactive than alkali metals. In the middle ages "earth" was any solid substance that did not melt and was not changed by fire into some other substance. Because many alkaline earth compounds have high melting temperatures and the same general appearance. These high temperatures were not attainable by those people, hence, the name "earth" was applied and stuck till today.
Halogens
Fluorine (F), Chlorine (Cl), Bromine (Br), Iodine (I), and Astatine (At)
Fluorine and chlorine are gases at room temperature. Bromide is a liquid and iodine is a sold. By themselves, all of these elements are diatomic (other elements that are diatomic but not a Halogen include oxygen and nitrogen). The name "halogen" comes from a Greek word, meaning "salt producing". The most well known salt produced by a halogen is sodium chloride (NaCl), also commonly known as table salt.
Fluorine and chlorine are gases at room temperature. Bromide is a liquid and iodine is a sold. By themselves, all of these elements are diatomic (other elements that are diatomic but not a Halogen include oxygen and nitrogen). The name "halogen" comes from a Greek word, meaning "salt producing". The most well known salt produced by a halogen is sodium chloride (NaCl), also commonly known as table salt.
Noble Gases
Helium (He), Neon (Ne), Argon (Ar), Krypton (Kr), Xenon (Xe), and the radioactive Radon (Rn)
Noble gases are colourless, monatomic gases at room temperature. Noble gases' valance shell are "full", therefor they rarely participate in chemical reactions. They are referred to as "noble" because this lack of chemical reactivity. Until 1962, it was thought that noble gases had no chemical reactivity at all.
Noble gases are colourless, monatomic gases at room temperature. Noble gases' valance shell are "full", therefor they rarely participate in chemical reactions. They are referred to as "noble" because this lack of chemical reactivity. Until 1962, it was thought that noble gases had no chemical reactivity at all.