Question

Uranium hexafluoride, UF\(_{6}\), is processed to produce fuel for nuclear reactors and nuclear weapons. UF\(_{6}\) is made from the reaction of elemental uranium with \(\mathrm{ClF}_{3},\) which also produces \(\mathrm{Cl}_{2}\) as a by-product. (a) Write the balanced molecular equation for the conversion of U and \(\mathrm{ClF}_{3}\) into UF \(_{6}\) and \(\mathrm{Cl}_{2}\) . (b) Is this a metathesis reaction? (c) Is this a redox reaction?

Short answer

The balanced chemical equation for the reaction is 3U + 6ClF3 → 3UF6 + 9Cl2. This is not a metathesis reaction since no ions are exchanged between molecules. However, it is a redox reaction since the oxidation state of uranium changes from 0 to +6, and the oxidation state of chlorine in ClF3 changes from +3 to -1.

Step-by-step solution

Writing the unbalanced chemical equation

The unbalanced chemical equation is formed by writing the reactants and products: U + ClF3 → UF6 + Cl2

Balancing the chemical equation

To balance the chemical equation, make sure the number of each element is the same on both sides: 3U + 6ClF3 → 3UF6 + 9Cl2 Now, the chemical equation is balanced. For the second part (b), we need to determine if this reaction is a metathesis reaction.

Identifying if a metathesis reaction has occurred

A metathesis reaction involves the exchange of ions between two reactants. In this case, there are no ions being exchanged since the reactants and products are all neutral molecules. Therefore, this is not a metathesis reaction. For the third part (c), we need to determine if this is a redox reaction.

Identifying if a redox reaction has occurred

A redox reaction involves a change in the oxidation state of one or more elements. To determine if this is a redox reaction, we must assign oxidation states to the elements involved: Uranium (U): 0 to +6 Chlorine in ClF3: +3 to -1 (in Cl2) Fluorine in ClF3: -1 to -1 (in UF6) In this reaction, the oxidation state of uranium increases from 0 to +6 while the oxidation state of chlorine in ClF3 decreases from +3 to -1. Therefore, this is a redox reaction.

Key concepts

Uranium Hexafluoride Production

The production of uranium hexafluoride (UF₆) is vital for the nuclear industry, as it is a key compound in the process of fuel fabrication for reactors and manufacturing nuclear weapons. The creation of UF₆ is initiated through the chemical reaction between elemental uranium and chlorine trifluoride (ClF₃). In this reaction, ClF₃ acts as a fluorinating agent, providing fluorine atoms to bond with uranium atoms and form UF₆, while yielding chlorine gas (Cl₂) as a by-product.

To produce UF₆, precise industrial processes are required where controls are in place to correctly handle both the reactants and the products due to their toxic and reactive nature. The safety protocols and environmental considerations are of utmost importance in this type of chemical production.

Balancing Chemical Equations

Balancing chemical equations is a fundamental skill in chemistry that ensures the law of conservation of mass is obeyed in a chemical reaction. This law states that matter cannot be created or destroyed in a closed system, implying that the number of atoms for each element must be the same on both sides of the equation.

To balance a chemical equation, you typically follow these steps: Identify each element present in the reactants and products, count the number of atoms of each element on both sides, and adjust coefficients in front of the chemical formulas to achieve the same number of each type of atom on both sides.

In the uranium hexafluoride production equation, the balancing act involves ensuring that there are equal numbers of uranium, chlorine, and fluorine atoms before and after the reaction. As you can see from the solution, coefficients are used strategically to achieve this balance. Understanding and practicing this process can help one grasp complex chemical reactions across all fields of chemistry.

Redox Reaction

A redox reaction, short for reduction-oxidation reaction, represents a chemical process where the oxidation states of atoms are changed. This involves the transfer of electrons between substances. A substance that loses electrons is oxidized, and its oxidation state increases, whereas the substance that gains electrons is reduced, and its oxidation state decreases.

In the case of the reaction between uranium and chlorine trifluoride, we can identify the changes in oxidation states of uranium and chlorine to confirm that it's indeed a redox process. Uranium's oxidation state increases from 0 in its elemental form to +6 in UF₆. Meanwhile, chlorine's oxidation state decreases from +3 in ClF₃ to -1 in Cl₂. The unchanging oxidation state of fluorine in ClF₃ and UF₆ shows it does not participate in the redox portion of the reaction.

Understanding redox reactions is crucial for studying various branches of chemistry, including electrochemistry, metallurgy, and biochemistry, since these reactions are foundational to processes such as energy generation, material corrosion, and metabolic pathways.