Answer to Question #201524 in General Chemistry for lea

Question

1. The soda cans used in this experiment are coated with a combination of paint and a protective polymer to protect the Aluminum from the acidic contents of soda. Describe how you could evaluate the total mass of the coating material on the can?
2. Would this technique be useful on a sample known to be made of pure Al? What about a sample of Al coated with a different metal such as Zinc?
3. A large water tank is used to equalize the level of liquid inside the buret and the liquid level outside the buret. If this step is skipped, how would the difference in volume affect the final mass of Al and your percent purity?
4. Zinc is also fairly reactive with HCl. Write a chemical equation and suggest a factor that would need to be considered for this experiment if the soda cans where made from Zinc?

Answer 1

1.Every soda can has a hidden liner inside to prevent the beverage from reacting with the metal.

2.High yield strength: Aluminium is one of the most ductile metals on earth. It affects yield strength positively.Oxidation resistance: The aluminium coating forms two layers that protect the steel core. On the very surface, a thin aluminium oxide layer is formed.

3.Equalizing the water levels equalizes the pressures and ensures that the total pressure in the flask is atmospheric and does not contain a contribution from the pressure due to the height of the water column.

4.When zinc reacts with hydrochloric acid it produces zinc chloride and hydrogen gas.