organization of the periodic table
DESCRIPTION
Organization of the Periodic Table. Groups. By Ms Dobbs. Group 18 = Noble gases. also know as inert gases very unreactive -- No known stable compounds have been produced from He, Ne, Ar. Xe Kr, and Rn have extremely low reactively , and will form compounds under extreme conditions. - PowerPoint PPT PresentationTRANSCRIPT
Organization of the Periodic Table
Groups
By Ms Dobbs
Group 18 = Noble gases
• also know as inert gases
• very unreactive -- No known stable compounds have been produced from He, Ne, Ar. Xe Kr, and Rn have extremely low reactively , and will form compounds under extreme conditions.
• 8 electrons in the outer most energy levels (filled s and p orbital)
Noble Gases
• Because of this e- configuration, noble gases are very stable and resist combining with other elements.
• Other elements gain or lose e- to achieve electron configuration like the noble gases.
• Noble gases are used in signs (Ne, Ar) and balloons (He).
• Rn is the only radioactive gas at room T/P.
Noble Gases
Group 1 = Alkali Metals
• Name comes from the Arabic work al-qali meaning ashes because it was discovered these elements make alkali (basic) solutions.
• Very reactive metals
• Will react with oxygen in air and must be stored in jars of oil or kerosene.
• Very soft and can be cut with a knife
Alkali Metals
• Have one electron in the outermost electron energy level (s)
• This electron configuration is what makes the metals so reactive.
• Are good conductors of electricity.
Alkali Metals
Alkali Metals
This sample of uraninitecontains some franciumbecause of a steady-statedecay chain. An estimatesuggests there is about 10-20 grammes of francium(about 1 atom!) at any onetime.
Group 2=Alkaline Earth Metals
• Tend to be harder, denser, stronger, and have high melting points than group 1
• Reactive but not has reactive as alkali metals
• have 2 electrons in outermost electron energy level (s)
Alkaline Earth Metals
• This electron configuration is what makes this group reactive.
• Conduct electricity
Alkaline Earth Metals
Alkaline Earth Metals
Groups 3-12=Transition Elements
• All are considered metals• Are harder, denser, and have
higher melting points than Groups 1 and 2
• Hg is the exception• These will conduct electricity.
Mercury: liquid at room Tlow melting point
Group 17 = Halogens
• Most are gases
• very reactive
• will combine with group 1 elements very readily
• 7 electrons in their outermost electron energy level (s and p)
Halogens
• This electron configuration is what makes the elements reactive.
• Halogens do not conduct electricity.
Halogens
Halogens
This sample of uranite containsa vanishingly small amountof astatine. The longest-livedisotope, 210At, has a half-lifeof only 8.3 hours. There areabout 20 isotopes known, allof which are radioactive.Astatine is a halogen andpossibly accumulates in thethyroid like iodine.
Groups 1,2,13-18 = Main Block Elements
• These represent a wide range of chemical and physical prop.
• Si and O account for 4 out of 5 atoms on Earth’s surface.
Lanthanide Series
• Elements 57 thorough 71.
• These are shiny, reactive, metals.
• These have electrons in the 4f orbital.
Lanthanide Series
Actinide Series
• Elements 89 through 103
• All have an unstable arrangement of protons and neutrons
• This makes them radioactive
Actinide Series
This sample ofuraninite containssome about 10-9 g ofactinium at any one time.
Hydrogen: group unto itself
• Most common element in the universe
• Behaves like no other element
• will react with just about any other element
• rarely found uncombined
Hydrogen