The alkaline earth metals are a group of elements located in the second group (Group 2) of the periodic table. These elements include beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). They are called 'alkaline earth' metals because they form alkaline compounds (compounds with a pH greater than 7) when they react with water, and because they were originally found in earths and were not associated with acidic compounds.The alkaline earth metals are characterized by their metallic properties and are highly reactive. They are solid at room temperature, with a shiny, silvery-white color. They have low densities and melting points, and are relatively soft and can be easily cut with a knife.Beryllium is the lightest of the alkaline earth metals, and it is the only one that is not radioactive. It is a strong and lightweight metal that is used in aerospace and defense applications, as well as in the manufacture of electronic devices and nuclear reactors. Magnesium is the next lightest of the group, and it is widely used in the production of alloys and in the aerospace, automotive, and construction industries. Calcium is the most abundant of the group and is an essential element for living organisms. It is also used in the production of cement, lime, and fertilizers.The remaining alkaline earth metals, strontium, barium, and radium, are not as commonly used as the first three. Strontium is used in fireworks and flares, while barium is used in the production of glass and ceramics. Radium, which is radioactive, is used in medical treatments and in certain types of research.In conclusion, The alkaline earth metals are a group of elements located in the second group of the periodic table and includes beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra).