The Periodic Table

• Different types of atoms are called?

  Elements
• Elements are made up of one type of atom
• How many known elements are there?

  118
• Elements can have different numbers of protons and electrons. This explains all of the differences in the physical properties of matter
• Dmitri Ivanovich Mendeleev - a Russian scientist who invented the Periodic Table in 1869
• All elements are listed and organized in a chart called the Periodic Table
• Each element sits in a specific place in the grid, according to its ATOMIC NUMBER
• Atomic number - the number of protons that an atom contains
• Metals are positioned to the left of the table, metalloids are in the middle, and nonmetals are positioned to the right
• Each element on the periodic table is assigned a CHEMICAL SYMBOL, which is one or two letters long
• Atomic mass - the average mass of a typical atom in that element
• Identify the parts

  A) Atomic number

  B) Element symbol

  C) Element name

  D) Atomic mass

  
• Period - the row of elements across the periodic table (horizontal)
• Group or Family - a column of elements in the periodic table. They have similar physical and chemical properties
• The periodic table is organized by rows and columns. A horizontal row is called a PERIOD. A vertical column is called a GROUP or FAMILY. The structure of the table is based on mass
• Neutral element - the number of protons equals the number of electrons. This means that the element has no charge
• The atomic number tells you the number of protons. If the element is neutral, it also tells you the number of electrons
• Number of Neutrons = Atomic mass - atomic number
• Common elements we use everyday

  1. Aluminum (AL) is used in making planes, pots, and pans
  2. Gold (AU) is used to make jewelry, and diamonds are composed of carbon
  3. Sodium (NA) is combined with chlorine (CI) to make table salt
  4. Neon (NE) is used to make neon signs
  5. Iron (FE) is used to make steel girders for bridges or buildings
• Isotopes - atoms with the same element
• Isotopes - always have the same number of protons with different atomic masses
• Each isotope of an element is identified with a MASS NUMBER
• Mass number - the sum of the atomic number and neutrons in the nucleus
• Isotopes - are always composed of the same element
• Isotopes - have different mass number and number of neutrons
• Isotopes - share the same chemical property but they differ in nuclear property
• The atomic number is equal to the number of protons

  TRUE
• The mass number is the sum of the number of protons and neutrons

  TRUE
• Isotopes are composed of the same element

  TRUE
• Isotopes have the same atomic number

  TRUE
• Isotopes share the same mass number

  FALSE
• Isotopes have the same number of neutrons

  FALSE
• Isotopes differ in number of protons

  FALSE
• Isotopes possess different chemical properties

  FALSE
• Isotopes possess different nuclear properties

  TRUE
• If an atom has a charge it is called ION
• A negatively charged ion or ANION, results when an atom gains one or more electrons
• A positively charge ion or CATION, results when an atom loses or gives away one or more electrons