Question

In: Chemistry

Part A: For a different reaction, Kc = 9.93, kf=421s−1, and kr= 42.4 s−1 . Adding...

Part A:

For a different reaction, Kc = 9.93, kf=421s−1, and kr= 42.4 s−1 . Adding a catalyst increases the forward rate constant to 1.35×105 s−1 . What is the new value of the reverse reaction constant, kr, after adding catalyst?

Part B:

Yet another reaction has an equilibrium constant Kc=4.32×105 at 25 ∘C. It is an exothermic reaction, giving off quite a bit of heat while the reaction proceeds. If the temperature is raised to 200 ∘C , what will happen to the equilibrium constant?

answers: equilibrium constant will:

a. increase

b. decrease

c. not change

Solutions

Expert Solution

part A

un catalyst                                    catalyst

Kf   = 421sce^-1                           Kf1 = 1.35*10^5 sec^-1

Kr   = 42.4sec^-1                          Kr1   =

Kf/Kr   = Kf1/Kr1

421/42.4   = 1.35*10^5/kr1

Kr1          = 1.35*10^5*42.4/421

                 = 1.35*10^4 sec^-1

The new value of the reverse reaction constant, kr, after adding catalyst is = 1.35*10^4 sec^-1

Part B

Every 10C^0 the equilibrium constant increases two or three times.

The equilibrium constant is directly propotional to temperature.

   The temperature is increases equilibrium constant is increases.

a. increase


Related Solutions

The generic reaction 2A?B has the following rate laws: forward reaction:reverse reaction:rate=kf[A]2rate=kr[B] where kf is the...
The generic reaction 2A?B has the following rate laws: forward reaction:reverse reaction:rate=kf[A]2rate=kr[B] where kf is the rate constant for the forward reaction and kr is the rate constant for the reverse reaction. At equilibrium, the two rates are equal and so kf[A]2=kr[B]. The equilibrium constant for a reaction is related by the law of mass action to the rate constants for the forward and reverse reactions: Kc=[B][A]2=kfkr Formation of nitrosyl bromide Nitrosyl bromide, NOBr, is formed in the reaction of...
Calculate the Kc for the following reaction at 25 °C: Mg(s) + Pb2+(aq)?Mg2+(aq) + Pb(s) Kc...
Calculate the Kc for the following reaction at 25 °C: Mg(s) + Pb2+(aq)?Mg2+(aq) + Pb(s) Kc = × 10 Enter your answer in scientific notation.
At 1000 K, the value of Kc = 0.032 for the reaction: C(s) + H2O(g) ⟺...
At 1000 K, the value of Kc = 0.032 for the reaction: C(s) + H2O(g) ⟺ CO(g) + H2(g) Calculate the equilibrium concentrations of H2O, CO, and H2 in a reaction mixture obtained by heating 6.05 mol of (H2O) steam and excess of solid carbon in a 5.90 L container.
The equilibrum constant Kc is 0.01323 for the reaction: CCl4 (g) <----> C(s) + 2 Cl2...
The equilibrum constant Kc is 0.01323 for the reaction: CCl4 (g) <----> C(s) + 2 Cl2 (g) At 300k a 5L flask originally contained 0.0828M of CCl4, 0.0444 M of C and 0.0546M of Cl2. Determine the concentration of Cl2 when equilibrium is reached.
For the reaction shown here, Kc = 0.513 at 500 K. N2O4(g)⇌2NO2(g) Part A If a...
For the reaction shown here, Kc = 0.513 at 500 K. N2O4(g)⇌2NO2(g) Part A If a reaction vessel initially contains an N2O4 concentration of 5.50×10−2 M at 500 K, what are the equilibrium concentrations of N2O4 and NO2 at 500 K? [N2O4], [NO2] =
Consider the reaction: NiO (s) + CO (g) <=> Ni (s) + CO2(g) Kc=4.0*10^3 (at 1500...
Consider the reaction: NiO (s) + CO (g) <=> Ni (s) + CO2(g) Kc=4.0*10^3 (at 1500 K) If a mixture of 1.00 mol nickel (II)oxide and 0.20 mol carbon monoxide in 2.00 L flask are allowed to come to equilibrium, what is the equilibrium concentration of carbon dioxide?
Write equations for the reaction of each substance in oxygen if a reaction occurs: 1. Adding...
Write equations for the reaction of each substance in oxygen if a reaction occurs: 1. Adding glowing orange wooden splint to oxygen and it relighting. 2. Adding glowing orange steel wool to oxygen and it sparkling. 3. Adding glowing orange charcoal to oxygen and relit 4. Adding burnt sulfur to oxygen and it relighting with blue flame
Consider the following reaction and associated equilibrium constant: aA(g)⇌bB(g), Kc = 4.0 Part A Find the...
Consider the following reaction and associated equilibrium constant: aA(g)⇌bB(g), Kc = 4.0 Part A Find the equilibrium concentrations of A and B for a=1 and b=1. Assume that the initial concentration of A is 1.0 M and that no B is present at the beginning of the reaction. Express your answers using two significant figures separated by a comma. [A], [B] =   M   Part B Find the equilibrium concentrations of A and B for a=2 and b=2. Assume that the...
Consider the following reaction and associated equilibrium constant: aA(g)⇌bB(g), Kc = 1.5 Part A Find the...
Consider the following reaction and associated equilibrium constant: aA(g)⇌bB(g), Kc = 1.5 Part A Find the equilibrium concentrations of A and B for a=1 and b=1. Assume that the initial concentration of A is 1.0 M and that no B is present at the beginning of the reaction. Express your answers using two significant figures separated by a comma. [A], [B] = ?M Part B Find the equilibrium concentrations of A and B for a=2 and b=2. Assume that the...
The equilibrium constant, Kc , for the following reaction is 5.10×10-6 at 548 K. NH4Cl(s) NH3(g)...
The equilibrium constant, Kc , for the following reaction is 5.10×10-6 at 548 K. NH4Cl(s) NH3(g) + HCl(g) If an equilibrium mixture of the three compounds in a 6.76 L container at 548 K contains 3.14 mol of NH4Cl(s) and 0.452 mol of NH3, the number of moles of HCl present is _________moles.
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT