Question

question 10 (1 point)
when the temperature iin a system in which the forward reaction is ii,
equilibrium shifts toward iii formation.
the statement given above is completed by the information given in the row:

row	i	ii	iii
b	increases	exothermic	product
c	increases	endothermic	reactant
d	decreases	endothermic	product
e	decreases	exothermic	reactant

○ a
○ b
○ c
○ d
○ e

question 11 (1 point)
when a catalyst is added to a chemical system involving a reversible reaction, the
catalyst __________.
○ increases the rate of reaction in both directions
○ increases the rate of reaction in the forward direction only
○ increases the rate of reaction in the reverse direction only
○ has no effect on the rate of reaction in either direction
○ shifts equilibrium in one direction

question 12 (1 point)

Explanation:

Question 10

• According to Le - Chatelier's principle, for an endothermic forward reaction (\(\Delta H>0\)), when the temperature increases, the system will try to consume the added heat. Since the forward reaction is endothermic (absorbs heat), increasing the temperature will shift the equilibrium towards the product side (to absorb the extra heat).

• A catalyst lowers the activation energy (\(E_a\)) for both the forward (\(E_{a,\text{forward}}\)) and reverse (\(E_{a,\text{reverse}}\)) reactions. The rate of a chemical reaction is related to the activation energy by the Arrhenius equation \(k = A\mathrm{e}^{-E_a/RT}\), where \(k\) is the rate constant, \(A\) is the pre - exponential factor, \(R\) is the gas constant, and \(T\) is the temperature. Since the activation energy for both directions is lowered, the rate of reaction in both directions (forward and reverse) is increased. A catalyst does not change the position of the equilibrium (it affects the kinetics, not the thermodynamics of the reaction).

Answer:

A. increases, endothermic, product

Question 11