Explaining energy changes in reactions - Higher

• What is the difference between exothermic and endothermic reactions?

  Exothermic reactions release energy, while endothermic reactions absorb energy.
• What happens to the temperature of the surroundings during an exothermic reaction?

  The temperature of the surroundings increases.
• What happens to the temperature of the surroundings during an endothermic reaction?

  The temperature of the surroundings decreases.
• What is the process of energy transfer in exothermic and endothermic reactions?

  • Exothermic reactions:
  • Energy is given out
  • Surroundings gain energy
  • Endothermic reactions:
  • Energy is taken in
  • Surroundings lose energy
• What is the unit of energy measurement mentioned in the study material?

  Joules (J)
• If a man transfers 100 J of energy while moving a wheelbarrow, how much energy is he transferring?

  100 J
• What occurs during a chemical reaction regarding bonds?

  Bonds in the reactants are broken and new bonds are formed in the products.
• What is a reactant?

  A substance that reacts with another substance to form products during a chemical reaction.
• What is a product?

  A substance formed in a chemical reaction.
• How is the type of reaction determined in terms of energy changes?

  It is determined by the difference between the energy needed to break bonds and the energy released when new bonds are made.
• What characterizes an exothermic reaction in terms of bond energy?

  More heat energy is released in making bonds in the products than is taken in when breaking bonds in the reactants.
• What characterizes an endothermic reaction in terms of bond energy?

  Less heat energy is released in making bonds in the products than is taken in when breaking bonds in the reactants.
• What are the types of processes associated with breaking and forming bonds?

  • Breaking bonds: Endothermic process
  • Forming bonds: Exothermic process
• How do exothermic and endothermic reactions differ in terms of energy transfer?

  Exothermic reactions give out energy, while endothermic reactions take in energy.
• What is the significance of the energy changes in chemical reactions?

  They determine whether a reaction is exothermic or endothermic.