chemistry paper 1

• mixture


  composed of two or more substances together but not chemically combined.
• evaporation


  can be used to separate a soluble solid from a liquid e.g salt and water
• chromatography


  is a technique used to separate substances carrying them different distances in a solvent along chromatography paper.
• distillation


  This method can be used to separate a soluble solid from a liquid just like evaporation
• filtration


  This is a method used to separate an insoluble solid from a liquid.
• solute


  a solid substance that is dissolved in a solution.
• solvent


  In a solution, the substance in which the solute dissolves.
• soluble


  this is when something dissolves in a solvent
• insolube


  this is when it doesn't dissolve in a solvent
• periodic Table


  achart of the elements showing the repeating pattern of their properties

  
• How is the periodic table arranged?

  by atomic number (number of protons)
• mendeleev


  A Russian chemist. He is credited as being the primary creator of the first version of the periodic table of elements. Though there were other contributors to the table, Mendeleev predicted the properties of elements yet to be discovered.
• Groups or Families


  The vertical columns on periodic table. These elements have similar chemical and physical properties.

  
  

  The elements in each group have the same number of electrons in the outer orbital (*see valence electrons)
• Periods


  Each horizontal row on the periodic table is called a period. Elements in periods are not alike in properties. First element in a period is always extremely active and the last is always an inactive gas

  
  

  All of the elements in a period have the same number of energy levels/orbitals.
• Alkali Metals


  Group 1

  1 valence electron

  +1 charge

  Very reactive

  Form (+) ions

  Metals (shiny, conduct electricity, ductile)

  
• Alkali Earth Metals


  Group 2

  2 valence electrons

  +2 charge

  Form (+) ions

  Metals (shiny, conduct electricity, ductile)

  
• Halogens


  Group 17

  7 valence electrons

  -1 Charge

  Form (-) ions

  Nonmetals

  
• Noble Gases


  Group 18

  8 valence electrons

  0 charge (no charge)

  Do not react with other

  
• valence electrons


  Electrons on the outermost energy level of an atom.

  These are the electrons that are gained or lost when bonds are formed.
• Metals


  Characteristics such as malleable, ductile, shine and conductivity
• Nonmetals


  Elements that are usually dull in appearance, poor conductors of heat and electricity, gases at room temperature
• Metalloids


  Elements that have properties of both metals and nonmetals.

  
  

  Elements along the stair-step line:

  B, boron; Si, Silicon; Ge, germanium;

  As, arsenic; Sb, antimony;

  Te, tellurium; Po, polonium; At, astatine
• all the flashcards with groups are pictures .
• group 1

  
• group 2

  
• group 3

  
• group 4

  
• group 5

  
• group 6

  
• group 7

  
• group 8

  
• metal


  Elements that are good conductors of heat and electric current.

  
• nonmetal


  an element that conducts heat and electricity poorly

  
• gas


  A state of matter with no definite shape or volume

  
• liquid


  A state of matter that has no definite shape but has a definite volume.

  
• noble gases


  the elements in Group 8 of the periodic table

  
• Atomic Number


  Number of protons in an atom

  
• Atomic Mass


  total weight of protons and neutrons

  
• atom


  smallest unit of matter

  
• nucleus of atom


  the positively charged dense center of an atom