12Groups / FamiliesGroups or families are the vertical columns on the periodic table.These elements have the same number of electrons in their outer orbits.They also have many characteristics in common.The group IIa elements; beryllium, magnesium, calcium, strontium, & barium. They are called the Alkali Earth Metals.
13Groups / Families Which elements are these? upper left – magnesium lower right - calciumWhat do they have in common?The same number of electrons in their outer orbit.
14Groups / FamiliesGroup VIIa is the Halogen family; fluorine, chlorine, bromine, & iodine.What do all of these elements have in common?Each has 7 electrons in its outer orbit.What characteristics do they have in common?All are very toxic and used as germ killers.
15Alkali Metal Family Each has only one electron in it’s outer orbit Soft metals that rapidly corrode when exposed to airReact violently with waterPart of many common salts
16Alkali Earth Metals Have 2 electrons in their outer orbits. Highly reactive and corrosive metals.Magnesium is found in abundance in sea water.Calcium is important for bones and teeth.
17Halogens Selected Properties of the Group 7 Halogens Symbol and Name Atomic NumberElectron arrangementState and color at room temperature, color of vapor when heatedMelting pointBoiling pointFFluorine92.7-220oC, 53K-188oC 85KCl Chlorine172.8.7-101oC, 172K -34oC, 239KBr Bromine35-7oC, 266K59oC, 332KIIodine53114oC, 387K185oC, 458KAt Astatine85302oC 575K337oC 610Kblack solid, very dark vapourdark red liquid, orange to bromine vapourpale yellow gasgreen gasvery dark grey solid, purple vapour
18Noble or Inert Gases Have full outer orbits. Are gases at room temperature.They rarely form compounds. Inert!!Helium is the second most abundant element in the cosmos.
19Periods Periods are the horizontal rows on the periodic table. Elements in the same period have the same number of orbits containing electrons.These elements do not have many other characteristics in common.