The periodic table

• in the modern periodic table, elements are arranged in order of increasing atomic number
• what do periods mean in the periodic table?

  rows
• what do groups mean in the periodic table?

  columns
• how many periods does the periodic table have?

  7
• how many groups does the periodic table have?

  18
• hydrogen is not part of alkali metals
• alkali metals have 1 valence electron
• alkali metals form ions with a charge of +1
• alkali earth metals have a charge of +2
• alkaline earth metals have 2 valence electrons
• alkaline earth metals can conduct electricity
• group 3-12 is called Transition Metals
• boron family forms ions with a charge of +3
• boron family has 3 valence electrons
• the carbon family form ions with a charge of +4
• the carbon family has 4 valence electrons
• the carbon family contains elements that can form unusual bonds

  (carbon,silicon)
• the nitrogen family are also known as chalcogens
• the oxygen family forms ions with a charge of -2
• the oxygen family has 6 valence electrons
• the nitrogen family has an ion charge of -3
• the nitrogen family has 5 valence electrons
• the halogens form ions with a charge of -1
• the halogens are the most reactive nonmetals
• the halogens have 7 valence electrons
• noble gases are nonreactive
• noble gases are also called inert gases

  true
• noble gases do not form ions
• which noble gas has 2 valence electrons

  helium
• noble gases have 8 valence electrons
• noble gases are gases
• dimtri was the first scientist to notice the relationship between elements
• dimtri arranged his table by atomic mass
• who predicted aluminum

  dimtri mendeleev
• periodic table has 18 families
• what are the 3 classes of elements

  metals, nonmetals, metalloids
• Mendeleev arranged the elements in his periodic table in order of increasing atomic mass. true or false?

  true