Question

Suppose the reaction system $$\mathrm{UO}_{2}(s)+4 \mathrm{HF}(g) \rightleftharpoons \mathrm{UF}_{4}(g)+2 \mathrm{H}_{2} \mathrm{O}(g)$$,has already reached equilibrium. Predict the effect that each of the following changes will have on the equilibrium position. Tell whether the equilibrium will shift to the right, will shift to the left, or will not be affected. a. Additional UO \(_{2}(s)\) is added to the system. b. The reaction is performed in a glass reaction vessel; \(\mathrm{HF}(g)\) attacks and reacts with glass. c. Water vapor is removed.

Short answer

The effect of the given changes on the equilibrium position are as follows: a. Adding additional UO\(_{2}(s)\) will have no effect on the equilibrium position because the concentration of a solid is constant and unchanged. b. When HF(g) reacts with the glass reaction vessel, the equilibrium will shift to the left to counteract the decrease in HF(g) concentration. c. The removal of water vapor will cause the equilibrium to shift to the right to compensate for the decrease in H\(_{2}\)O(g) concentration.

Step-by-step solution

Write the equilibrium reaction

We are given the following equilibrium reaction system: \[ \mathrm{UO}_{2}(s) + 4 \mathrm{HF}(g) \rightleftharpoons \mathrm{UF}_{4}(g) + 2 \mathrm{H}_{2} \mathrm{O}(g) \] Now we can analyze the effect of the given changes on this equilibrium system. #Step 2: Analyze the effect of adding additional UO\(_{2}(s)\).#

Analyze the effect of adding additional UO\(_{2}(s)\)

Since UO\(_{2}(s)\) is a solid, its concentration is constant and unaffected by the amount present in the system. Adding more UO\(_{2}(s)\) does not change its active concentration in the reaction. Therefore, there is no effect on the equilibrium, and the equilibrium position does not shift. #Step 3: Analyze the effect of the reaction between HF(g) and the glass reaction vessel.#

Analyze the effect of the reaction between HF(g) and the glass reaction vessel

The reaction between HF(g) and the glass reaction vessel leads to the consumption of HF(g). This results in a decrease in the concentration of HF(g). According to Le Châtelier's principle, the equilibrium will shift in the direction that counteracts this change, which is the direction where HF(g) is formed. In our case, that direction is towards the reactants. Therefore, the equilibrium will shift to the left. #Step 4: Analyze the effect of removing water vapor.#

Analyze the effect of removing water vapor

When the water vapor is removed, the concentration of H\(_{2}\)O(g) decreases. According to Le Châtelier's principle, the system will respond by shifting the equilibrium to counteract this change, which means shifting the equilibrium in the direction where H\(_{2}\)O(g) is formed. In our case, that direction is towards the products. Therefore, the equilibrium will shift to the right.

Key concepts

Le Châtelier's Principle

Le Châtelier's Principle is a foundational concept in chemistry, particularly when discussing chemical equilibrium. It states that if a system at equilibrium is subjected to a change, the system will adjust itself to counteract that change and restore a new equilibrium. This principle is vital for understanding how different factors can influence the direction of a chemical reaction.

For example, a change could be the addition or removal of a reactant or product, a change in temperature or pressure, or the introduction of a catalyst. The principle helps predict the direction in which the equilibrium will shift to accommodate the change.

In the reaction given, when HF gas reacts with the glass vessel and reduces HF concentration, Le Châtelier's Principle predicts a shift toward the reactants to make more HF, thus shifting the equilibrium left. Conversely, removing water vapor shifts equilibrium towards products as the system compensates by forming more water, thus shifting it right.

Equilibrium Shift

An equilibrium shift refers to a change in the position of an equilibrium in response to an external disturbance. The shift can be to the right (toward products) or to the left (toward reactants), depending on what change is introduced.

In the case of the reaction \[ \mathrm{UO}_{2}(s) + 4 \mathrm{HF}(g) \rightleftharpoons \mathrm{UF}_{4}(g) + 2 \mathrm{H}_{2} \mathrm{O}(g) \]adding more UOdefines an equilibrium shift:

• Adding solids like UOdefines an equilibrium shift:
  • Adding solids like UO
  - leaves the equilibrium unaffected since solids do not impact concentration
  • Reducing HF concentration shifts equilibrium left
  • Removing water vapor shifts equilibrium right
  
  Understanding these shifts helps in predicting how a reaction can be manipulated or controlled within industrial or laboratory settings to maximize desired products.

Reaction System Analysis

Analyzing a reaction system involves examining the components and their behavior under various conditions to understand how the system behaves at equilibrium. It's crucial to take into account all aspects such as types of reactants and products, phase of components, and external conditions.

For the reaction \[ \mathrm{UO}_{2}(s) + 4 \mathrm{HF}(g) \rightleftharpoons \mathrm{UF}_{4}(g) + 2 \mathrm{H}_{2} \mathrm{O}(g) \]consider:

• The phases: UO