rates of reaction

• Rate of reaction = amount of reactant used or amount of product formed / time taken
• Gas syringe experiment

  1. add a set volume of dilute hydrochloric acid (HCL) to a conical flask
  2. add some magnesium ribbon to acid and quickly attach the gas syringe to flask
  3. start stopwatch and take readings of the volume of gas at regular intervals
  4. plot results on graph
  5. repeat experiment 3 times, then repeat again using different concentrations of HCL
• Cloudy precipitate test

  1. sodium thiosulfate and HCL are both clear solutions, but react together to form a yellow precipitate called sulfur
  2. add a set volume of dilute sodium thiosulfate to conical flask, and place flask on a sheet of paper with a black cross on it
  3. add some dilute HCL and start stopwatch
  4. measure how long it takes for the cross to disappear
  5. repeat 3 times, then repeat with different concentrations of either HCL or sodium thiosulfate (one or the other)