During this lab you will be using Skittles to represent molecules in photosynthesis and respiration. The law of conservation of matter states that matter is neither created nor destroyed, it only changes form. You will see that during photosynthesis and respiration the atoms in the reactants will equal the atoms in the products. You will also learn the reactants and products for photosynthesis and respiration. Direction: 1. Decide what color Skittle you are going to use to represent each kind of atom. _____________ Carbon _____________ Hydrogen _____________ Oxygen 2. Complete the chart below using the chemical equations for photosynthesis and respiration. (Remember: Respiration occurs in mitochondria, the energy powerhouse of the cell.) Photosynthesis: 6CO2 + 6H2O à C6H12O6 + 6O2 Respiration: C6H12O6 + 6O2à 6CO2 + 6H2O Reactants (needed)
Products (given off)
Photosynthesis Respiration
3. How many total atoms of carbon are there in the reactants of photosynthesis? _______________ 4. How many total atoms of hydrogen are there in the reactants of photosynthesis? _______________ 5. How many total atoms are of oxygen are there in the reactants of photosynthesis? _______________ 6. Place the color Skittle you chose on all of the atoms of the reactants of photosynthesis. For example, if you chose red for Carbon, put a red Skittle on all the C’s. 7. In photosynthesis, water and carbon dioxide change into oxygen and glucose. Take the carbon Skittles you used for your reactants and put them on all the carbon atoms on the product side of the equation. 8. Do the same thing for oxygen and hydrogen.
9. How many total atoms of carbon are there in the products of photosynthesis? _____________ 10. How many total atoms of hydrogen are there in the products of photosynthesis? _____________ 11. How many total atoms of oxygen are there in the products of photosynthesis? _____________ 12. Repeat the process above but simulate the chemical process of respiration. (Turn the model of molecules paper over.) Conclusion: 13. What did you observe while doing this activity about photosynthesis and respiration? ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 14. What is the conservation of matter? ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________ 15. How was the conservation of matter demonstrated in this lab? ________________________________________________________________________ ________________________________________________________________________ ________________________________________________________________________
