element of group Any of the divalent electropositive metals beryllium, magnesium, calcium, strontium, barium, and radium, belonging to group 2A of the periodic table; alkaline earth metals
element of group Group IV consists of two subgroups: group IVb, main group, and group IVa. Group IVa consists of titanium, zirconium, and hafnium which are generally classified as transition metals. The main group consists of carbonium, silicium, germanium, tin, and lead. The main valency of the elements is IV, and the members of the group show a variation from nonmetallic to metallic behaviour in moving down the group. The reactivity of the elements increases down the group from carbon to lead. All react with oxygen on heating
element of group Group VI consists of two subgroups: group VIb, the main group, and group VIa. Group VIa consists of chromium, molybdenum, and tungsten. The main group consists of oxygen, sulphur, selenium, tellurium, and polonium
element of group Any of the monovalent metals lithium, sodium, potassium, rubidium, caesium, and francium, belonging to group 1A of the periodic table. They are all very reactive and electropositive; alkaline
element of group Group III consists of two subgroups: group IIIb and group IIIa. Group IIIa consists of scandium, yttrium, and lanthanium, which is generally considered with the lanthanoids, and actinium, which is classified with the actinoids. Group IIIb, the main group, comprises boron, aluminium, gallium, indium, and thallium
element of group Group V consists of two subgroups: group Vb, the main group, and group Va. Group Va consists of vanadium, niobium, and tantalum, which are generally considered with the transition elements. The main group consists of nitrogen, phosphorus, arsenic, antimony, and bismuth
