Science - Endothermic and Exothermic Reactions

  1. What is an exothermic reaction?
    These are chemical reactions that give out heat so the temperature increases eg. coal burning to heat a room and fireworks exploding

    Exothermic = energy exits
  2. What is an endothermic reaction?
    These are chemical reactions that take in heat causing a decrease in temperature eg. sherbet on your tongue and using an instant cold pack to reduce swelling

    Endothermic = energy enters
  3. What are energy profile diagrams?
    These show energy transfers in chemical reactions
  4. What is collision theory?
    This happens before a chemical reaction when the particles in the reactants must collide with each other

    The more collisions the faster the reaction will take place

    Low concentration = few collisions

    High concentration = more collisions
  5. What is activation energy?
    This is the minimum energy needed to start a reaction
  6. What is meant by rate of reaction?
    This describes how quickly a chemical reaction happens
  7. Describe how temperature affects the rate of a reaction
    Raising the temperature increases the rate of a reaction

    As heat is added to a reaction, the particles that make up the reactants gain more kinetic energy and move faster
  8. Describe how concentration of the reactants affects the rate of a reaction
    Increasing the concentration of reactants increases the number of particles in a given volume

    Low concentration results in fewer collisions

    High concentration results in more collisions
  9. Describe how surface area of the reactants affects the rate of a reaction
    Increasing the surface area increases the rate of a reaction ie. as a particle size gets smaller, the surface area increases

    If you cut a potato into smaller pieces it will cook quicker than cooking a whole potato
  10. Describe how adding a catalyst affects the rate of a reaction
    A catalyst speeds up the rate of a chemical reaction

    It lowers the amount of energy needed for a reaction to happen which makes it easier for the particles to react so there is an increase in the rate of reaction
Author
mshowley
ID
340435
Card Set
Science - Endothermic and Exothermic Reactions
Description
Endothermic and Exothermic Reactions
Updated