Chemistry: Periodic Table of Elements

periods

-The horizontal rows of elements in the periodic table -Horizontal row 1 is called the first period (it contains H and He); row 2 is called the second period (elements Li through Ne); and so on.

Groups / Families

-a vertical column of elements having the same valence electron configuration and showing similar properties. 1A, 2A, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13(3A), 14(4A), 15(5A), 16 (6A), 17(7A), 18(8A)

Group 1A

-alkali metals -made up of lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr) -members of group 1A are very active elements that readily form ions with a 1+ charge when they react with nonmetals.

Group 2A

-alkaline earth metals -made up of beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra)—are called the alkaline earth metals. -members of group 2A all form ions with a 2+ charge when they react with nonmetals.

halogens

-group 17(7A) -made up of fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At) -halogens all form diatomic molecules. Fluorine, chlorine, bromine, and iodine all react with metals to form salts containing ions with a 1− charge (F⁻, Cl⁻, Br⁻, and I⁻).

noble gases

-group 18(8A) -made up of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn) -noble gases all exist under normal conditions as monatomic (single-atom) gases and have little chemical reactivity.

alkali metals

-group 1A -made up of lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs), and francium (Fr) -are very active elements that readily form ions with a 1+ charge when they react with nonmetals.

alkaline earth metals

-group 2A -made up of beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra)—are called the alkaline earth metals. -all form ions with a 2+ charge when they react with nonmetals.

Group 17(7A)

-halogens -made up of fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At) -members of group 7A all form diatomic molecules. Fluorine, chlorine, bromine, and iodine all react with metals to form salts containing ions with a 1− charge (F⁻, Cl⁻, Br⁻, and I⁻).

Group 18(8A)

-noble gases -made up of helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn) -members of group 8A all exist under normal conditions as monatomic (single-atom) gases and have little chemical reactivity.

(Table 2.2)

Current name / Original Name / Symbol Antimony / Stibium / Sb Copper / Cuprum / Cu Iron / Ferrum / Fe Lead / Plumbum / Pb Mercury / Hydrargyrum / Hg Potassium / Kalium / K Silver / Argentum / Ag Sodium / Natrium / Na Tin / Stannum / Sn Tungsten / Wolfram / W

What are the characteristics of metals?

Metals have characteristic physical properties such as efficient conduction of heat and electricity, malleability (they can be hammered into thin sheets), ductility (they can be pulled into wires), and (often) a lustrous appearance. Chemically, metals tend to lose electrons to form positive ions. For example, copper is a typical metal. It is lustrous (although it tarnishes readily); it is an excellent conductor of electricity (it is widely used in electrical wires); and it is readily formed into various shapes, such as pipes for water systems. Copper is also found in many salts, such as the beautiful blue copper sulfate, in which copper is present as Cu²⁺ ions. Copper is a member of the transition metals—the metals shown in the center of the periodic table.

What is the most common type of element?

Most of the elements are metals.

What are the letters in the boxes of the periodic table?

The letters in the boxes are the symbols for the elements; these abbreviations are based on the current element names or the original names (Table 2.2)

What is the number shown above each symbol?

The number shown above each symbol is the atomic number (number of protons) for that element.

How is the periodic table arranged?

The periodic table is arranged so that elements in the same vertical columns (called groups or families) have similar chemical properties.

What are the characteristics of nonmetals?

The relatively few nonmetals appear in the upper-right corner of the table (to the right of the heavy line in Fig. 2.19), except hydrogen, a nonmetal that resides in the upper-left corner. The nonmetals lack the physical properties that characterize the metals. Chemically, they tend to gain electrons in reactions with metals to form negative ions. Nonmetals often bond to each other by forming covalent bonds. For example, chlorine is a typical nonmetal. Under normal conditions it exists as Cl₂ molecules; it reacts with metals to form salts containing Cl₂ ions (NaCl, for example); and it forms covalent bonds with nonmetals (for example, hydrogen chloride gas, HCl).

periodic table

a chart showing all the elements arranged in columns with similar chemical properties

What are the different types of elements?

alkali metals alkaline earth metals transition metals halogens noble gases *lanthanides *actinides

nonmetals

an element not exhibiting metallic characteristics. Chemically, a typical nonmetal accepts electrons from a metal.

Metal(s)

an element that gives up electrons relatively easily and is lustrous, malleable, and a good conductor of heat and electricity.