Particle size

• Apparatus + chemicals needed: electronic balance, conical flask, graduated cylinder, stopwatch, marble chips, cotton, hydrochloric acid

  1. Measure the total mass of the marble chips, cotton, grad. cylinder and conical flask on the balance.
  2. Place the HCl in the flask along with the marble chips, and start the stopwatch. Carbon dioxide is produced from this reaction.
  3. Place the cotton on the flask and take down the mass of all of the apparatus every 30 seconds.
  4. Repeat the experiment with different sizes of marble chips
• Word formula:

  • Calcium carbonate + hydrochloric acid -> Calcium chloride + water + carbon dioxide
• Chemical formula:

  • CaCO3 + 2HCl -> CaCl2 + H2O + CO2
• The carbon dioxide can be tested for by bubbling it through limewater. The lime water goes from colourless to a milky colour.