- Even though bones are very light, they are also very strong, how strong they are depends on how much of mineral calcium carbonate they contain. Eggs ans bones contain calcium carbonate (CaCO3).
In this experiment will be create the bones more flexible.
Objectives:
- Identify mineral salts in organisms.
- Understand the function of inorganic biomolecules in skeletal structures of organisms.
Procedure:
Bones:
- Cut ad much of the meat away from the chicken thin bone as possible.
- Examine the flexibility of the bone.
- We put the bones inside the beaker.
- We took a beaker and we put: 200ml of water and 200ml of acid acetic or vinegar.
- We cover the beaker to protect the solution and we need to leave it 24 hores to know what happens to the bone.
Observations of bones:
The bone is more flexible because lose the ridigity with the acid or vinagre.Shells:
- We took another beaker and put water and calcium carbonate.
- We put inside some shells.- We saw a lot of bubbles.
Obervations of the shells:
- Three hours later we saw that the shells were floating, and the meaning of this is that the shells are less dense than the water.REACTION:
HCL + CaCo3------> CO2 + CaCl2
QUESTIONS:
1. Write the reaction that takes place when the acid acetic reacts with the calcium carbonate.
Answer: bubbles
2. What is happening the shells are soaking of acetic acid? What are the bubbles you can see?
Answer: bubbles are formed. The bubbles are carbon dioxide.
3. What is happening to the bone after some days of soaking it in acetic acid? Why is the bone flexible now?
Answer: the bone is more flexible, and they leave it the ridigity .
4. So, what is the function of the calium carbonate in the skeletal structures?
Answer: Rigidity.
5. Increases in carbon dioxide to the atmosphere from the burning fossil and deforestation threaten to change the chemistry of the seas. Evidence suggests that this increase in atmospheric carbon dioxide is lowering the pH of the oceans in a process called ocean acidification. How can acidification affects corals reefs?
Answer: The reefs coral will be dissolve because the pH will be reduce of the corals.
