Periodic Table Groups and Trends. The Main-Group Elements. Elements in Groups 1a, 2a, and 3a-8a are known as the main group elements. Main group elements are in the s-block and the p-block. The electron configurations of these are regular and consistent.
Main group elements are in the s-block and the p-block.
The electron configurations of these are regular and consistent.
The elements in each group have the same number of valence electrons.
All Alkali Metals are extremely reactive.
They are usually stored in oil to keep them from reacting with the oxygen and water found in the air.
(They are very
likely to lose
a positive ion.
they can easily be cut with a knife.
The freshly cut surface of an alkali metal is shiny, but it dulls quickly as the metal reacts with oxygen and water in the air.
strontium, barium, and
Beryllium is found in emeralds, which is a variety of the gemstone beryl.
Bones are made primarily of calcium phosphate.
Marble is made of calcium carbonate.
These include fluorine,
chlorine, bromine, iodine,
Sodium (an alkali metal) will easily react with Chlorine (a halogen) to form sodium chloride (NaCL), table salt.
These consist of Helium, Neon, Argon, Krypton, Xenon and Radon
One example of the power of this reaction occurred in 1937 when the German airship, the Hindenberg burst into flames while trying to land in Lakehurst, New Jersey. 38 people were killed in the explosion.
In this Periodic Table, all of the elements shown in blue are metals.
characteristics of both
metals and non-metals.
They conduct electricity
better than non-metals,
but not as good as metals.
metals are good conductors
of heat and electricity. They
are also ductile and malleable.
Some metals are so un-reactive, they seldom form compounds with other elements. Examples are Gold, Platinum, and Palladium (AKA: precious metals). Other than the noble gases, these three are the most un-reactive atoms and most often exist in nature as pure elements.
because their atomic numbers
follow the element lanthanum.
Lanthanide oxides: clockwise from top center: praseodymium, cerium, lanthanum, neodymium, samarium and gadolinium.
The nuclear bomb dropped on Nagasaki to end WWII had a plutonium charge.
Glenn T. Seaborg and his group at the University of California at Berkeley synthesized Pu, Am, Cm, Bk, Cf, Es, Fm, Md, No and element 106, which was later named seaborqium in his honor while he was still living.
Because there are more and more electrons shielding the outer electrons from the +-charged nucleus, it is easier to strip off electrons from the outer energy level. Therefore, ionization energy decreases.
Ionization Energy increases because it takes MORE energy to pull electrons away from an atom with more protons.
of protons pulls the
electrons closer to the
nucleus, which makes
the atom slightly
smaller (even though
there are more electrons!)
Electron shielding makes it less likely that a larger atom can attract an electron.