1.2 Mineral salts in organisms

Introduction:
In this experiment we worh with bones and shells.
The bones are very light, they are olso very strong, and are depens on how much of mineral calcium carbonated (CaCO3) they contain, and shells with the acetic acid was dissolvented.
What we do in this experiment is that the bone are more flexibility and the shells melt.

Materials:
-shells
-bones
-water
-acetic acid
-tongs
-2 * 600mL beaker
-clock glass
-mineral salts
-safety goggles
-cloridric acid

Objectives
-Identify minerals salts in organisms.
-Understant the function of inorganic biomolecules in skelet structures of organisms.

Procedure:
A) Bones:
1- Carefully clean and cut ad much of the meat away from the chiken thin bone as possible.
2- Examine the flexibility of the bone by trying to bend it with your fingers.
3- Take a beaker and make and acid acetic solution or add vinegar.
4- Take the chicken or lamb bones and drop them in the acid acetic solution thet you have made.
5- Leave it 24 hours and see whats happens to the bone. Put a clock glass at the top of the beaker to protect the solution.
6- Remove the bones fromthe vinegar with a tongs and soak them with water.
7- Write the results in your lab worksheet.



B) Shells:
1- Take another beaker and make the same acid acetic solution.
2- PUt inside some shells and make note of what is happening.
3- Write the observation in your lab worksheet.

Observation of bones
The bone is more flexibility because lose the ridigity with the vinegar, there are now only
collagen.










REACTIONS: HCl + CaCO3 ·········> CO2 +CaCl2

Observation of shells
The shells was dissolveted.



Questions
1-Writethe reaction that takes place when the acid acetic reacys with the calcium carbonate.
Bubbles.
2-What happening when the shells are soaking of acetic acid? What are the bubbles that you can see?
Bubbles was formed, this was carbon dioxide.
3-What is happening to the bone after some days of soaking it in acetic acid? Why is the bone flexible now?
The bone is more flexible.
4-So, what is the function of the calcium carbonated in the skelet structures?
Rigidity.
5-Increases in carbon dioxide to the atmosphere from the burning fossil fuels and deforestation threaten to change the chemistry of the seas. Evidence suggests thet this increases in atmospheric carbone dioxide is lowering the pH of the oceans in a process called ocean acidification. How can acidification affects coral reefs?
The coral reefs will be dissolve.