reactions

• What are the observations a chemical reaction

  has taken place?

  • Bubbles/fizzing (gas produced)

  • Colour change or new solid formed

  • Energy change
• How do you describe an exothermic reaction?

  A chemical reaction which releases

  energy to the surroundings
• What happens to the temperature

  during an exothermic reaction?

  The temperature increases
• How do you describe an endothermic

  reaction?


  A chemical reaction which absorbs

  energy from the surroundings
• What happens to the temperature

  during an endothermic reaction?

  The temperature decreases\
• What does a catalyst do?


  Speeds up the rate

  (speed) of reaction
• Why can a catalyst be used

  several times?

  Catalysts are not used up during a reaction
• Combustion is the scientific term for:

  burning
• in combustion Endo or exothermic

  exothermic
• What gas is required for fuels to undergo

  combustion?

  oxygen
• Complete this complete combustion word

  equation: ethanol -


  water + carbon dioxide
• In exothermic reactions, is energy released or absorbed

  released
• In endothermic reactions, is energy released or absorbed

  absorbed
• When a compound is heated and it breaks down

  into smaller compounds, it is referred to as

  thermal decomposition
• Complete this word equation: calcium = calcium oxide +


  carbon dioxide
• calcium carbonate = calcium oxide + carbon dioxide.......................................... Is this reaction exothermic or endothermic?

  endothermic
• What is the chemical test for carbon dioxide?

  bubble it through limewater and it turns cloudy
• balance mg + 02 = mgO

  2mg + 02 = 2mgO
• balance C3H8 + O2 = CO2 + H2O


  C3H8 + 5 O2 = 3 CO2 + 4 H2O
• What is meant by the term ‘conservation of

  mass’?

  Mass is not lost or gained during a reaction
• What is the state symbol for solid 


  (s)
• What is the state symbol for gas


  (g)
• What is the state symbol for gas


  (g)
• what is the state symbol for dissolved in water

  (aq)