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• Draw and label an atom

  Protons

  Neutrons

  Electrons

  
• What are the masses and charges of these parts of an atom?

  
  

  • Proton

  • Neutron

  • Electron

  Protons = +e

  (mass 1)

  
  

  Neutrons = neutral

  (mass 1)

  
  

  Electrons = -e

  (mass 1/2000th)
• Why do atoms usually have no overall electrical charge?

  Atoms usually have no overall charge because they have equal numbers of protons (+e) and electrons (-e), which cancel one another out
• All atoms of a particular element (e.g. carbon) all have the same number of what?

  Protons
• What does relative atomic mass tell you about the atom?

  The number of protons and neutrons in the atom
• What does atomic number tell you about the atom?

  The number of protons (usually the same as the number of electrons)
• What is an isotope?

  An isotope is an atom with a different amount of neutrons
• How many electrons can occupy the 1st and 2nd shell of an atom?

  1st shell: 2

  2nd shell: 8
• What does the electron structure 2,8,1 mean?

  2,8,1 means: 2 electrons in the 1st shell, 8 electrons in the 2nd shell and 1 electron in the 3rd shell
• Define these terms: -

  
  

  • Element

  • Compound

  • Mixture

  Element - a pure substance made from 1 type of atom only

  
  

  Compound - 2 or more elements chemically bonded

  
  

  Mixture - 2 or more elements or compounds mixed together which are not chemically bonded.
• What happens to the electrons of 2 atoms when they chemically react?

  During a chemical reaction electrons are either given away, taken, or shared
• What is an ion?

  An ion is an atom with a net charge; an atom or group of atoms that have one or more positive or negative charges.
• What happens to the electrons when atoms form ionic bonds and covalent bonds?

  
  

  Which is the strongest?

  Ionic bonds - 1 atom loses electrons and another gains electrons

  
  

  Covalent bonds - electrons are shared

  
  

  An individual covalent bond is stronger than an ionic bond
• What are the melting and boiling points of covalent compounds like?

  
  

  Explain why this is

  Covalent compounds have low melting and boiling points (are often gases) are there is no attraction between the molecules
• How are the elements of the periodic table arranged?

  
  

  What are the rows called?

  
  

  What are the columns called?

  Elements are arranged in order of atomic number

  
  

  Rows are called periods

  
  

  Columns are called groupsSee an expert-written answer!We have an expert-written solution to this problem!
• Why do elements in the same group have similar properties?

  Elements in the same group have similar properties as they all have the same number of electrons in their outer shell
• Why do covalent compounds not conduct electricity when dissolved?

  Covalent compounds do not conduct because they do no break down into ions
• Describe the bonding in metals:
• Which group of the periodic table do not form ions?

  
  

  Explain why this is

  Noble gases do not form ions as they already have a full outer shell
• What are the names of the following groups in the periodic table?

  
  

  • Group 1

  • Group 2

  • Middle metals

  • Group 7

  • Group 0

  Group 1 = alkali metals

  
  

  Group 2 = alkaline Earth metals

  
  

  Middle metals = transition metals

  
  

  Group 7 = halogens

  
  

  Group 0 = Nobel gases
• Why are metals easily shaped?

  Metals are easily shaped because the atoms are closely arranged and can slide past one another
• How can you calculate atomic mass?

  Add the relative atomic masses of the elements within the compound
• What is equilibrium?


  Equilibrium is reached when the reactions occur at exactly the same rate in both directions
• What type of salts are made from the following?

  
  

  • Hydrochloric acid

  • Sulfuric acid

  • Nitric acid

  Hydrochloric acid - chlorides

  
  

  Sulfuric acid - sulfates

  
  

  Nitric acid - nitrates
• What types of ions do the following form?

  
  

  • Metals

  • Non-metals

  Metals = +ve

  
  

  Non-metals = -ve
• How can a solid salt be obtained from a salt solution?

  Evaporating to leave the salt crystals
• Give 3 things which can increase the rate of a reaction?

  Temperature

  Concentration / pressure

  Surface area
• Why does temperature affect the rate of reaction?

  Increasing the temperature gives the particles increased energy - the particles move faster, colliding more often and with more force, increasing the rate of reaction.
• Why does concentration / pressure affect the rate of reaction?

  The higher the concentration of a liquid or the higher the pressure of a gas then the higher the rate of reaction due to the increased movement of particles.
• Why does surface area affect the rate of a reaction?

  The larger the surface area the more exposed particles there are to react
• What must happen for a reaction to take place?

  Particles must collide with enough force
• What is an exothermic reaction?


  A reaction which gives out energy (usually heat)
• What is an endothermic reaction?

  A reaction which takes energy in from the surroundings
• What is the independent variable?

  The independent variable is the variable that is changed
• What is the dependent variable?

  The dependent variable is the variable that is measured