Presentation on theme: "Periodic Table of Elements Dimitri Mendeleev Russian scientist 1869 noticed that he arranged elements by their atomic mass Present day periodic table."— Presentation transcript:
Dimitri Mendeleev Russian scientist 1869 noticed that he arranged elements by their atomic mass Present day periodic table arranged by atomic #
Period – Horizontal row on the Periodic Table Group/Family – Vertical column on the Periodic Table
Groups…Here’s Where the Periodic Table Gets Useful!! Elements in the same group have similar chemical and physical properties!! (Mendeleev did that on purpose.) They have the same number of valence electrons. They will form the same kinds of ions. Why ?
Groups are also called families. They are vertical columns.
Periods Row on the period table Elements in the same period have the same number of electron rings Very different properties as you move across the table Examples: Period 1 ~ H and He 1 electron shell Period 2 ~ Li, Be, B, C, N, O, F, 2 electron shells Etc……..
Periodic means having regular patterns or cycles that occur. Chemical symbols- first letter is always capitalized and the second letter is lower case. Elements names are often in different languages. Ex. Sodium (Na) latin word natrium
Alkali Metals 1 st column on the periodic table (Group 1) not including hydrogen. Very reactive metals Always combined with something else in nature (like in salt). Soft enough to cut with a butter knife 1 valence electron
Alkaline Earth Metals Second column on the periodic table. (Group 2) Reactive metals Always combined with nonmetals in nature. Several are important mineral nutrients (Mg and Ca) 2 valence electrons
Transition Metals Elements in groups 3-12 Less reactive harder metals Includes metals used in jewelry and construction. Metals used “as metal.”
Halogens Elements in group 17 Very reactive, volatile, diatomic, nonmetals Always found combined with other element in nature Used as disinfectants and to strengthen teeth