For the chemical reaction
`3X(g)+Y(g) hArr X_(3)Y(g)`,
the amount of `X_(3)Y` at equilibrium is affected by

Options

A. Temperature and pressure
B. Temperature only
C. Pressure only
D. Temperature, pressure, and catalyst

Answer

To determine how the amount of \( X_3Y \) at equilibrium is affected in the reaction

\[ 3X(g) + Y(g) \rightleftharpoons X_3Y(g), \]

we need to analyze the factors that influence chemical equilibrium.

### Step 1: Identify the reaction and its components
The given reaction involves three moles of gas \( X \) and one mole of gas \( Y \) on the reactant side, producing one mole of \( X_3Y \) on the product side.

### Step 2: Analyze the volume of gases
On the left side (reactants), we have a total of 4 moles of gas (3 moles of \( X \) + 1 mole of \( Y \)), while on the right side (products), we have only 1 mole of gas (\( X_3Y \)).

### Step 3: Consider the effect of pressure
According to Le Chatelier's principle, if we increase the pressure of a system at equilibrium, the equilibrium will shift towards the side with fewer moles of gas. In this case, increasing the pressure will favor the formation of \( X_3Y \) since it has fewer moles (1 mole) compared to the reactants (4 moles).

### Step 4: Consider the effect of temperature
The question does not specify whether the reaction is exothermic or endothermic. Therefore, we cannot definitively conclude how temperature affects the equilibrium position without that information. In general, for exothermic reactions, increasing temperature shifts the equilibrium to the left (towards reactants), while for endothermic reactions, it shifts to the right (towards products).

### Step 5: Consider the effect of a catalyst
A catalyst speeds up the rate of both the forward and reverse reactions equally, but it does not affect the position of the equilibrium. Therefore, the presence of a catalyst will not change the amount of \( X_3Y \) at equilibrium.

### Conclusion
From the analysis, we can conclude that the amount of \( X_3Y \) at equilibrium is primarily affected by changes in pressure. The correct answer is that the amount of \( X_3Y \) is affected by pressure only.

### Final Answer
The amount of \( X_3Y \) at equilibrium is affected by **pressure only**.

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