CFR: Chemical Equilibria and Physiological Consequences

A comprehensive set of flashcards on Chemical Equilibria and Physiological Consequences for exam preparation.

What is chemical equilibrium?

A state in a reversible reaction where the rates of forward and reverse reactions are equal and concentrations of reactants and products remain constant.

What does it mean when K << 1?

The reaction is reactant-favored, indicating that the concentrations of reactants are greater than those of products.

What does it mean when K >> 1?

The reaction is product-favored, indicating that the concentrations of products are greater than those of reactants.

Define dynamic equilibrium.

An equilibrium state in which forward and reverse reactions proceed at the same rate.

What is the equilibrium constant expression?

A ratio of the concentrations of products to reactants at equilibrium, each raised to the power of their respective coefficients.

What happens during a change in concentration according to Le Chatelier's principle?

The equilibrium shifts towards the side that reduces the change; increasing reactants shifts to products and vice versa.

How do temperature changes affect equilibrium in an exothermic reaction?

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

In the reaction 2 NO(g) + O2(g) ↔ 2 NO2(g), what is K?

K = [NO2]^2 / ([NO]^2 [O2]) for the given balanced reaction.

What occurs if pressure is increased in a gaseous equilibrium reaction?

The equilibrium shifts towards the side with fewer moles of gas.

What is Le Chatelier’s principle?

If an external stress is applied to a system at equilibrium, the system shifts to partially offset the applied stress.

Explain the concept of physical equilibrium.

An equilibrium between two phases, such as liquid water in equilibrium with its vapor.

Provide an example of equilibrium involving solids and liquids.

The concentration of solids and pure liquids is fixed and not included in the equilibrium expression.

What does the symbol Kc denote?

Kc denotes that equilibrium concentrations are in terms of molarity (moles per liter).

Describe the effect of catalysts on equilibrium.

Catalysts do not affect the position of equilibrium; they speed up the rates of both forward and reverse reactions equally.

In the bicarbonate buffer system, what happens during hyperventilation?

Hyperventilation reduces CO2 concentration, causing the equilibrium to shift to the left.

What is the impact of altitude on oxygen levels and hemoglobin?

At high altitudes, lower oxygen pressure leads to hypoxia, shifting hemoglobin equilibrium to the left.

How can K be calculated from concentration values at equilibrium?

K can be determined using equilibrium concentrations from a balanced chemical equation.

What is the general formula for K at equilibrium?

K_{eq} = rac{[G]^g[H]^h}{[A]^a[B]^b} where concentrations of products are in the numerator and reactants in the denominator.

What shift occurs if reactant concentration is decreased?

The equilibrium shifts to the left, towards the reactants.

When dealing with reactions involving gases, what unit is often used for Kp?

Kp is expressed in terms of pressure.

What is the reaction when calculating K from concentrations initially set at 0?

Set initial concentrations to zero, then apply the changes for equilibrium concentration.

Mention a physiological condition affecting bicarbonate equilibrium.

Increased lactic acid from exercise shifts the equilibrium to the right in the bicarbonate buffer.

What is the equilibrium approximation for gases?

Use partial pressures for gases in the equilibrium constant expression.

In equilibria, what does the term 'stoichiometric coefficients' refer to?

The coefficients in a balanced chemical equation that are used as powers in K expressions.

How is the K value affected by temperature?

K depends on the particular reaction and the temperature.

Explain the 'forward' and 'reverse' reactions concerning K.

The K for a reverse reaction is the reciprocal of the K for the forward reaction.

In the reaction CO + 2 H2 ↔ CH3OH, what type of system is it?

It is a closed system at dynamic equilibrium.

What effect does increased volume have on gaseous equilibrium?

Increased volume shifts equilibrium towards the side with more moles of gas.

What is the relationship between Kc and Kp?

Kc is for concentration, and Kp is for partial pressures; they are related through the ideal gas law.

What is an example of an external stress affecting equilibrium?

A change in temperature, concentration, or pressure applied to a system at equilibrium.

Define hypoventilation in terms of CO2 concentration.

Hypoventilation increases CO2 concentration, shifting bicarbonate equilibrium to the right.

Identify the equilibrium equation involving hemoglobin at high altitudes.

Hb + 4O_2
ightleftharpoons Hb(O_2)_4; equilibrium shifts left under hypoxic conditions.

How do catalysts influence the rate of consumption of reactants?

Catalysts speed up the reaction without being consumed, allowing reactants to convert to products faster.

What does an increase in the concentration of products cause the equilibrium to do?

It causes the equilibrium to shift toward the reactants.

What is the equilibrium constant for the reaction N2(g) + 3H2(g) ↔ 2NH3(g)?

K = [NH3]^2 / ([N2][H2]^3) for the balanced equation.

What is the significance of a reaction being product-favored?

It indicates that at equilibrium, products are favored over reactants, as shown by K >> 1.

During what condition does the equilibrium shift to the right in the blood buffer system?

Increased lactic acid concentration favors the production of H2CO3 and HCO3-.

What happens to the equilibrium of a reaction when pressure is decreased?

The equilibrium shifts toward the side with more moles of gas.

State the importance of writing K expressions correctly.

Writing K expressions accurately reflects the stoichiometry of the chemical reaction.

In determining K, why are solids and pure liquids excluded?

Their concentrations remain constant throughout the reaction and do not affect the equilibrium position.

What is the formula for calculating K for the reaction 2NOCl(g) ↔ 2NO(g) + Cl2(g)?

Kc = [NO]^2[Cl2] / [NOCl]^2 for the given reaction.

What physiological response occurs from a decrease in blood pH?

It can indicate an increase in acid levels, causing a shift in the bicarbonate buffer equilibrium.

What reaction results in altitude sickness?

Decreased O2 pressure leads to reduced hemoglobin affinity for oxygen and hypoxia.

How does one maximize the yield of NH3 in the Haber process?

Remove NH3 as it forms and increase the concentrations of N2 and H2 while managing pressure and temperature.

What is the purpose of a catalyst in a chemical equilibrium?

To speed up the reactions to reach equilibrium faster without affecting the position of the equilibrium.

What does a change in temperature do in exothermic reactions?

In exothermic reactions, an increase in temperature shifts the equilibrium position to favor reactants.