topic 6

Question 1

Chemical equilibrium, equilibrium constant, and the law of mass action:

Answer 1

Chemical Equilibrium:
occurs when the rates of the forward and reverse reactions in a reversible reaction are equal, and the concentrations of reactants and products remain constant over time./Even though concentrations remain constant, both forward and reverse reactions continue at equal rates./Influenced by temperature, pressure, and concentration of reactants and products.

Equilibrium Constant (K):

Definition: The equilibrium constant (K) is a numerical value that describes the ratio of concentrations of products to reactants at equilibrium, with each concentration raised to the power of its coefficient in the balanced chemical equation.
Expression: For the general reaction
aA+bB⇌cC+dD, the equilibrium constant is given by /Units: Depends on the specific reaction and the units of concentration used (e.g., mol/L for concentration terms).

Law of Mass Action:
states that the rate of a chemical reaction is directly proportional to the product of the concentrations of the reactants, each raised to the power equal to their respective coefficients in the balanced chemical equation, at a given temperature./Equilibrium Condition: At equilibrium, the rate of the forward reaction equals the rate of the reverse reaction.

The equilibrium constant expression is: K = ([C]^c [D]^d) / ([A]^a [B]^b)

Question 2

Le Chatelier’s Principle

Answer 2

states that if a system at equilibrium is subjected to a
change in temperature, pressure, or concentration of reactants or products, the system will shift to
counteract the imposed change and establish a new equilibrium. In other words, the system will
respond to stress by adjusting the concentrations of species to restore equilibrium

Question 3

Effects of Changing Reaction Conditions

Answer 3

Increasing temperature favors the endothermic direction (absorbs heat), while decreasing temperature favors the exothermic direction (releases heat). Increasing temperature favors the endothermic direction (absorbs heat), while decreasing temperature favors the exothermic direction (releases heat).

Increasing pressure shifts the equilibrium toward the side with fewer moles of gas (decreases volume), and decreasing pressure shifts it toward the side with more moles of gas (increases volume).

Increase in Reactants: Shifts equilibrium toward products.

Increase in Products: Shifts equilibrium toward reactants.

Question 4

Application of Le Chatelier’s Principle

Answer 4

Le Chatelier’s principle can be applied to various chemical
systems to predict how they respond to changes. It helps understand and optimize reaction
conditions in industries, such as the Haber process for ammonia synthesis and the contact process for
sulfuric acid production.

Question 5

Metathesis Reactions:

Answer 5

s involve the exchange of ions between reactants to form
new compounds. Common types include precipitation reactions (formation of a solid), gas formation
reactions, and neutralization reactions (formation of water and a salt

Question 6

Solubility Equilibrium and Solubility Product Constant:

Answer 6

Solubility equilibrium refers to the balance
between the dissolved and undissolved forms of a solute in a solvent. The solubility product constant
(Ksp) is the equilibrium constant for the dissolution of a sparingly soluble salt. It describes the
relationship between the concentrations of ions in a saturated solution of the salt and helps determine
the solubility of the salt in the solvent