The Haber process is very important for agriculture because it converts N₂(g) from the atmosphere into bound nitrogen, which can be taken up and used by plants. The Haber process reaction is N₂(g) + 3 H₂(g) → 2 NH₃(g). The reaction is exothermic but is carried out at relatively high temperatures. Why?

Verified step by step guidance

Understand the Haber process: The Haber process synthesizes ammonia (NH3) from nitrogen (N2) and hydrogen (H2) gases. The balanced chemical equation is N2(g) + 3 H2(g) → 2 NH3(g).

Recognize the nature of the reaction: The reaction is exothermic, meaning it releases heat.

Consider the effect of temperature on reaction rate: Higher temperatures increase the kinetic energy of molecules, leading to more frequent and effective collisions, thus increasing the reaction rate.

Apply Le Chatelier's Principle: Although the reaction is exothermic, increasing the temperature shifts the equilibrium position to favor the reactants (N2 and H2). However, high temperatures are used to achieve a reasonable reaction rate despite this shift.

Balance between rate and yield: The process is carried out at high temperatures to ensure a faster reaction rate, even though it slightly reduces the yield of ammonia due to the equilibrium shift.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Haber Process

The Haber process is a chemical reaction that synthesizes ammonia (NH3) from nitrogen (N2) and hydrogen (H2) gases. This process is crucial for producing fertilizers, which are essential for modern agriculture. The reaction is represented by the equation N2(g) + 3 H2(g) → 2 NH3(g), highlighting the stoichiometric relationship between the reactants and products.

Exothermic Reactions

An exothermic reaction is one that releases energy, usually in the form of heat, to its surroundings. In the context of the Haber process, although the reaction itself is exothermic, it is conducted at high temperatures to increase the reaction rate and overcome the activation energy barrier. This is a common practice in industrial chemistry to optimize production efficiency.

Le Chatelier's Principle

Le Chatelier's Principle states that if a dynamic equilibrium is disturbed by changing the conditions, the system will adjust to counteract the change and restore a new equilibrium. In the Haber process, high temperatures favor the formation of reactants (N2 and H2) over products (NH3), so the reaction is conducted at elevated temperatures to balance the rate of production and maintain efficiency.

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Le Chatelier's Principle

Related Practice

Textbook Question

Indicate and explain the sign of ΔS_univ for each process. a. 2 H₂(g) + O₂(g) → 2 H₂O (l) at 298 K.

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Textbook Question

Dinitrogen tetroxide decomposes to nitrogen dioxide: N₂O₄(g) → 2 NO₂(g) ΔH°_rxn = 55.3 kJ At 298 K, a reaction vessel initially contains 0.100 atm of N₂O₄. When equilibrium is reached, 58% of the N₂O₄has decomposed to NO₂. What percentage of N₂O₄decomposes at 388 K? Assume that the initial pressure of N₂O₄is the same (0.100 atm).

Textbook Question

A metal salt with the formula MCl₂ crystallizes from water to form a solid with the composition MCl₂ • 6 H₂O. The equilibrium vapor pressure of water above this solid at 298 K is 18.3 mmHg. What is the value of ΔG for the reaction MCl₂ • 6 H₂O(s) ⇌ MCl₂(s) + 6 H₂O(g) when the pressure of water vapor is 18.3 mmHg? When the pressure of water vapor is 760 mmHg?

Textbook Question

The solubility of AgCl(s) in water at 25 °C is 1.33⨉10^-5 mol/L and its ΔH° of solution is 65.7 kJ/mol. What is its solubility at 50.0 °C?