Kesetimbangan Kimia | Faktor Yang Mempengaruhi Pergeseran Kesetimbangan

Summary

In this video, viewers learn about factors affecting chemical equilibrium, focusing on Le Chatelier’s Principle. The host explains how changes in concentration, temperature, and pressure can shift the equilibrium of a reaction. Increasing concentration of a substance shifts equilibrium away from it, while temperature changes depend on whether the reaction is endothermic or exothermic. The video also covers how pressure and volume adjustments impact equilibrium, especially in reactions involving gases. Through practical examples and problem-solving, the video provides a clear understanding of equilibrium shifts and how to predict them based on these factors.

Takeaways

• 😀 Le Chatelier's principle states that a system at equilibrium will shift to counteract any changes in concentration, temperature, or pressure.
• 😀 If the concentration of a substance is increased, the equilibrium will shift away from that substance to reduce its concentration.
• 😀 Conversely, decreasing the concentration of a substance will shift the equilibrium towards that substance to increase its concentration.
• 😀 For heterogeneous equilibria, changes in concentration only affect substances that are in a liquid or gas phase, not solids or liquids.
• 😀 Temperature changes affect the equilibrium by shifting it towards the endothermic direction when heat is added, and towards the exothermic direction when heat is removed.
• 😀 If a reaction is endothermic (positive ΔH), the equilibrium shifts to the right when temperature increases and to the left when temperature decreases.
• 😀 If a reaction is exothermic (negative ΔH), the equilibrium shifts to the left with increasing temperature and to the right with decreasing temperature.
• 😀 Pressure changes affect gaseous equilibria by shifting the equilibrium towards the side with fewer gas molecules when pressure increases, and towards the side with more gas molecules when pressure decreases.
• 😀 For reactions involving gases, the number of gas molecules on each side of the equation determines the direction of equilibrium shift under pressure changes.
• 😀 The equilibrium constant (K) for endothermic reactions increases with temperature, while for exothermic reactions, it decreases as temperature increases.

Q & A

What is Le Chatelier's Principle and how does it apply to chemical equilibrium?

Le Chatelier's Principle states that if a system at equilibrium is disturbed by an external factor, the system will shift in a direction that counteracts the disturbance, thus trying to restore equilibrium.

How does increasing the concentration of a substance affect chemical equilibrium?

Increasing the concentration of a substance will cause the equilibrium to shift away from that substance, in order to reduce its concentration and reestablish balance.

What happens when the concentration of a substance is decreased in a reaction at equilibrium?

When the concentration of a substance is decreased, the equilibrium shifts towards that substance to counteract the decrease and increase its concentration.

Why does the effect of concentration changes only apply to gases and aqueous substances?

Concentration changes only affect gases and aqueous substances because they are able to mix or dissolve in a solution. Solids and liquids do not have the same dynamic behavior and therefore do not impact equilibrium shifts in the same way.

How does temperature affect the position of equilibrium?

If the temperature is increased, the equilibrium will shift towards the endothermic side (heat absorption), and if the temperature is decreased, it will shift towards the exothermic side (heat release).

What is the role of ΔH in determining whether a reaction is endothermic or exothermic?

ΔH (enthalpy change) tells us whether a reaction is endothermic or exothermic. A positive ΔH indicates an endothermic reaction, where heat is absorbed, and a negative ΔH indicates an exothermic reaction, where heat is released.

How do pressure and volume changes influence chemical equilibrium?

Pressure and volume are inversely related. If pressure increases (volume decreases), the equilibrium will shift toward the side with fewer gas molecules. If pressure decreases (volume increases), it will shift toward the side with more gas molecules.

Why is it important to consider the coefficients of gases when calculating equilibrium shifts?

The coefficients of gases are important because they determine the relative amounts of gas molecules on each side of the equation, which affects how pressure changes influence equilibrium shifts.

How can we predict the shift in equilibrium for a reaction where the number of gas molecules is the same on both sides?

If the number of gas molecules is the same on both sides of the equation, then changes in pressure and volume will not affect the equilibrium position.

In the given example, why does increasing temperature shift the equilibrium of an endothermic reaction to the right?

In an endothermic reaction, heat is absorbed. Increasing the temperature adds more heat to the system, which shifts the equilibrium to the right to absorb the excess heat and maintain balance.