Of course! Let's address each part of the question in detail.
### i. What is meant by the term dynamic equilibrium?
Dynamic equilibrium refers to a state in a reversible chemical reaction where the rate of the forward reaction equals the rate of the backward reaction. This means that the concentrations of the reactants and products remain constant over time, even though the reactions are still occurring. In simple terms, it's a balance where the formation of products (going forward) happens at the same rate as the reformation of reactants (going backward).
### ii. What is the effect of concentration, pressure, and temperature on the above equilibrium reaction?
For the reaction:
[tex]\[ \text{N}_2(g) + 3\text{H}_2(g) \rightleftharpoons 2\text{NH}_3(g) \Delta H = -92 \text{kJ mol}^{-1} \][/tex]
1. Concentration:
- Increasing the concentration of reactants (N₂ or H₂): This will shift the equilibrium to the right, favoring the formation of ammonia (NH₃). This is because the system will try to counteract the change by using up the extra reactants to form more products.
- Increasing the concentration of the product (NH₃): This will shift the equilibrium to the left, favoring the formation of nitrogen (N₂) and hydrogen (H₂). The system tries to counteract the increase in product concentration by decomposing some of it back into reactants.
2. Pressure:
- Increasing the pressure: This will shift the equilibrium to the side with fewer moles of gas. In this reaction, the right side (products) has fewer moles of gas (2 moles of NH₃) compared to the left side (reactants) which has 4 moles of gas (1 mole of N₂ and 3 moles of H₂). Therefore, increasing the pressure will favor the production of ammonia (NH₃).
3. Temperature:
- Decreasing the temperature: Since the reaction is exothermic (releases heat, ΔH = -92 kJ mol⁻¹), lowering the temperature will shift the equilibrium to the right, favoring the formation of NH₃. This is because the system will try to produce more heat to counteract the decrease in temperature.
- Increasing the temperature: In contrast, raising the temperature will shift the equilibrium to the left, favoring the decomposition of ammonia back to N₂ and H₂, because the system will try to absorb the excess heat by favoring the endothermic direction.
### iii. Give one fertilizer with the formula formed by ammonia.
One common fertilizer formed by ammonia is ammonium nitrate, with the chemical formula [tex]\( \text{NH}_4\text{NO}_3 \)[/tex]. Ammonium nitrate is widely used in agriculture due to its high nitrogen content, which is essential for plant growth.
