Science Experiment: Effect of Surface Area on the Rate of Reaction

Introductions

• Speakers:

  • Amelia: Lab technician and science ambassador at Sanctum School, Cambridge.
  • Guest: Excited to bring Science Hazel to the lab and conduct practical experiments.

• About Amelia:

  • Works at Sanctum School, promotes science among kids.
  • Active on Instagram with science experiments and videos (@amelie_about_science).

Objective

• Experiment: Investigate the effect of surface area on the rate of reaction.
• Materials Used: Calcium Carbonate (CaCO3)
  • Two forms: Chip form and powdered form.

Key Variables

• Independent Variable (IV): Surface area of calcium carbonate (chip vs. powdered form).
• Control Variables:
  • Starting mass of calcium carbonate.
  • Temperature of the reaction environment.
  • Concentration of hydrochloric acid (HCl).

Reaction Details

• Chemical Reaction:
  • Calcium Carbonate (CaCO3) reacts with Hydrochloric Acid (HCl).
  • Produces Calcium Chloride (CaCl2), Water (H2O), and Carbon Dioxide (CO2).

Experimental Setup

• Acid Concentration: 0.5 Molar (0.5M) HCl
• Volume of Acid Used: 25 ml

Procedure

1. Powdered Calcium Carbonate Experiment:

   • Measure 25 ml of 0.5M HCl.
   • Start the stopwatch and observe.
   • Produce 45 cm³ of CO2 in 30 seconds.

2. Chipped Calcium Carbonate Experiment:

   • Measure 25 ml of 0.5M HCl.
   • Start the stopwatch and observe.
   • Produce 5 cm³ of CO2 in 30 seconds.

Observations & Results

• Results Comparison:
  • Powdered form produced significantly more CO2 (45 cm³) compared to the chip form (5 cm³) in the same time frame.
  • Demonstrates that smaller surface area results in a slower rate of reaction compared to a larger surface area.

Calculations

• Rate of Reaction Calculation:
  • Rate = Change in volume of CO2 / Time
  • Rate for powdered form = 45 cm³ / 30 seconds.
  • Rate for chip form = 5 cm³ / 30 seconds.