Last minute Recall

• Suggest how copper sulfate can be used as a test for the presence of water

  • Add water to anhydrous copper sulfate
  • Colour changes from white to blue
• Why is obtaining potable water from salty water more expensive than obtaining potable water from ground water?

  • Distillation requires energy to boil salty water, whereas ground water only needs filtering and sterilising
• State 2 disadvantages of phytomining:

  • Slower process
  • Large area of land required
• Explain how a catalyst increases the rate of reaction

  • Provides an alternative pathway which has a lower activation energy
• What happens to the equilibrium position when the pressure increases?

  • Moves in the direction of the fewest molecules of gas to reduce the pressure
• If the forward reaction is exothermic, what happens to the equilibrium position if the temperature increases?

  • Moves in the endothermic direction (to the left) to reduce the temperature
• What happens to the equilibrium position if the concentration increases in one direction, e.g. the reactants?

  • Moves to the right near the products to make more of that product
• If one of the products is removed from a reaction on the right, what happens to the equilibrium position?

  Moves to the right to make more of that product