Classifying Elements Periodic Table Element Characteristics

Symbols All of the symbols have either one or two letters. The first letter of each symbol is a capital letter. If the symbol has a second letter, the second letter is a lowercase letter No period appears at the end of a symbol

Symbols Magnesium Helium Hydrogen Phosphorus Gold Mercury Zinc Copper Mg He H P Au Hg Zn Cu

Periodic Table Elements are arranged from left to right on the periodic table according to increasing atomic number. A group of elements with similar properties, arranged in a column is a family. A group of atoms of an element with the same number of protons and electrons, but different number of neutrons is an isotope. The average mass of all the isotopes of a particular element is the mass number.

Metals Most metals are solid at room temperature. Mercury is the only liquid metal. Most metals can be polished to look shiny. The shape of a metal can be changed, can be flattened into sheets or shaped into wires. Electricity and heat travel well through metals.

Metals On the periodic table, metals are found on the left side. Two or more metals mixed together is called an alloy. Column IA is the Alkali Metals, such as Li, Na, and K. Column IIA is the Alkali Earth Metals, such as Ca, Mg, and Be. Columns IIIB through IB are the Transition Metals, such as Ag, Au, Fe, and Ni. Elements and are the Rare Earth Metals

Nonmetals Most nonmetals are solids or gases at room temperature. They cannot be made into sheets, shaped into wires. They do not conduct heat and electricity well. Column VIIA is the Halogens, such as Cl, F, and Br.

Noble Gases Column VIIIA are called Noble or Inert Gases, such as He, Ne, and Kr. They do not react with other substances. They have eight electrons in their outer, or valence, energy level.

Metal, Nonmetal, or Noble Gas? Classify each as a metal, nonmetal, or noble gas. –C, Na, F, He, Ca Classify each as a metal nonmetal or noble gas. –Xe, Cl, K, Br, Mg Classify each as a metal, nonmetal, or noble gas. –Rn, Li, Ra, I, O

Reactivity Metals are more reactive further to the left and to the top of the periodic table. –Example: Na is more reactive than Mg, but Li is more reactive than Na. Nonmetals are more reactive further to the right and to the bottom of the periodic table. –Example: Cl is more reactive than S, but Br is more reactive than Cl.

Reactivity Place the elements in order of most reactive to least reactive. –K, H, Ca, Mg, Sr, Na, Li Place the elements in order of most reactive to least reactive. –O, F, P, Br, Cl, S, N