Equilibrium Chemistry

These flashcards cover key concepts and principles related to chemical equilibrium, including definitions, equilibrium expressions, and factors affecting equilibrium.

What does equilibrium in chemistry refer to?

It refers to the extent of a chemical reaction, indicating how much of the reactants and products are present.

How is the speed of a reaction related to equilibrium?

Kinetics describes how fast a reaction occurs, while equilibrium describes how much of the reactants and products are present.

What can we calculate with equilibrium constants?

We can calculate equilibrium constants in terms of concentration and pressure.

What is the equilibrium constant expression for aA + bB ⇌ cC + dD?

K = [C]^c [D]^d / [A]^a [B]^b.

What does it mean if K ≫ 1?

It indicates that products are favored at equilibrium.

For the reaction 2 H2O ⇌ 2 H2 + O2, what is the equilibrium constant expression?

K = [H2]^2 [O2] / [H2O]^2.

How does changing reaction coefficients affect K?

If the coefficients are multiplied by a constant factor, K must be raised to that power.

What happens to the reaction when pressure is increased in gas phase reactions?

It shifts towards the side with fewer moles of gas.

What role does temperature play in endothermic reactions at equilibrium?

Increasing temperature shifts the equilibrium towards products; decreasing temperature shifts towards reactants.

How does adding a catalyst affect equilibrium?

Adding a catalyst does not change the equilibrium position; it only speeds up the rate at which equilibrium is reached.

What is the significance of the reaction quotient Q?

Q compares the current concentrations of reactants and products to those at equilibrium to predict the direction of the reaction.

What does it mean if $K \ll 1$?

It indicates that reactants are favored at equilibrium.

How does adding or removing reactants/products affect equilibrium?

Adding reactants or removing products shifts the equilibrium towards the products; removing reactants or adding products shifts it towards the reactants.

What is Le Chatelier's Principle?

Le Chatelier's Principle states that if a change of condition (such as temperature, pressure, or concentration of reactants/products) is applied to a system in equilibrium, the system will shift in a direction that relieves the stress.

How does adding an inert gas affect equilibrium at constant volume?

Adding an inert gas at constant volume does not affect the concentrations or partial pressures of the reactants and products, so it has no effect on the equilibrium position.

What is the relationship between $K<em>p$ and $K</em>c$?

$K<em>p = K</em>c (RT)^{\Delta n}$, where $R$ is the ideal gas constant, $T$ is the absolute temperature, and $\Delta n$ is the change in the number of moles of gas (moles of gaseous products - moles of gaseous reactants).