Question

This is the writing prompt

The Case of the Sunken Treasure
Scientific Background:
After a decade of searching, a group of explorers finds the remains of the USS Minnow on the bottom of the ocean floor. Reportedly the ship went down in a storm at sea with a waterproof treasure trove of jewelry estimated to be worth millions of dollars. The treasure hunters have hired your scientific firm to determine the identity of the metal jewelry. Your team received 10.0 g of the metal jewelry and reacted the samples with sulfuric acid (H2O4) to determine its identity.
Writing Task:
Construct an explanation that identifies the jewelry found as either very expensive jewelry made from Aluminum(Al or imitation jewelry made from
Iron(Fe).

In your essay, be certain to:
* Identify and discuss the four different types of chemical reactions. Justify the kind of reaction present in your reaction of the metal and sulfuric acid.
* Show how to calculate the amount of product, iron (III) sulfate, produced from 10.0 grams of iron. Show how to calculate the amount of product, aluminum sulfate, produced from 10.0 grams of aluminum.
* Discuss what scientists can expect to see during the reaction. Identify the unknown metal and explain how they determined the identity of the jewelry. (Documents A through D are related to this Writing Task.)

Answer 1

Based on the scientific background provided, the jewelry found could potentially be made of either aluminum or iron. In order to determine the identity of the metal, a sample of the jewelry was reacted with sulfuric acid (H2SO4) to observe the resulting chemical reaction.

There are four different types of chemical reactions: synthesis reactions, decomposition reactions, single displacement reactions, and double displacement reactions. The reaction between the metal jewelry and sulfuric acid is a single displacement reaction, also known as a redox reaction. This is because the reaction involves the transfer of electrons from the metal to the hydrogen in the sulfuric acid.

The chemical equation for the reaction between the metal and sulfuric acid is:

Metal + H2SO4 → Metal sulfate + H2

If the metal is iron, the product produced is iron (III) sulfate (Fe2(SO4)3) and hydrogen gas (H2). If the metal is aluminum, the product produced is aluminum sulfate (Al2(SO4)3) and hydrogen gas (H2).

To calculate the amount of product produced, we need to use stoichiometry. Assuming the metal is iron, the molar mass of iron is 55.85 g/mol and the molar mass of iron (III) sulfate is 399.88 g/mol. Therefore, the theoretical yield of iron (III) sulfate from 10.0 g of iron is:

10.0 g Fe × (1 mol Fe / 55.85 g Fe) × (1 mol Fe2(SO4)3 / 2 mol Fe) × (399.88 g Fe2(SO4)3 / 1 mol Fe2(SO4)3) = 357.67 g Fe2(SO4)3

Similarly, if the metal is aluminum, the molar mass of aluminum is 26.98 g/mol and the molar mass of aluminum sulfate is 342.15 g/mol. Therefore, the theoretical yield of aluminum sulfate from 10.0 g of aluminum is:

10.0 g Al × (1 mol Al / 26.98 g Al) × (1 mol Al2(SO4)3 / 2 mol Al) × (342.15 g Al2(SO4)3 / 1 mol Al2(SO4)3) = 634.97 g Al2(SO4)3

During the reaction, scientists can expect to see bubbling as hydrogen gas is produced. They can also observe the color and texture of the metal before and after the reaction to help determine its identity. Once the product of the reaction is identified as either iron (III) sulfate or aluminum sulfate, the identity of the metal can be determined.

In conclusion, the reaction between the metal jewelry and sulfuric acid is a single displacement reaction. Assuming the metal is iron, the product produced is iron (III) sulfate, and if the metal is aluminum, the product produced is aluminum sulfate. Using stoichiometry, the theoretical yield of each product can be calculated. Scientists can observe the reaction and the resulting product to determine the identity of the metal.