Book: KE & R: 17

Question 1

Defining equilibrium in terms of reaction rates.

Answer 1

At equilibrium: rate_fwd = rate_rev

Question 2

Defining the equilibrium constant for the reaction A ⇌ 2B.

Answer 2

K = k_fwd / k_rev = [B_eq]^2 / [A_eq]

Question 3

Defining the equilibrium constant in terms of the reaction quotient.

Answer 3

At equilibrium: Q = K

Question 4

Expressing Q_c for the reaction aA + bB ⇌ cC + dD.

Answer 4

Q_c = ( [C]^c [D]^d ) / ( [A]^a [B]^b )

Question 5

Finding K of a reaction from K of the reverse reaction.

Answer 5

K_fwd = 1 / K_rev

Question 6

Finding Q and K of a reaction multiplied by a factor n.

Answer 6

Q’ = Q^n = ( [C]^c [D]^d ) / ( [A]^a [B]^b )^n and K’ = K^n

Question 7

Finding the overall K for a reaction sequence.

Answer 7

K_overall = (K_1) (K_2) …

Question 8

Relating K based on pressures to K based on concentrations.

Answer 8

K_p = K_c (RT)^(∆n_gas)

Question 9

Assuming that ignoring the concentration that reacts induces no significant error.

Answer 9

[A_init] - [A_reacting]= [A_eq] ≈ [A_init]

Question 10

Finding K at one temperature given K at another (van’t Hoff equation).

Answer 10

ln ( K_2 / K_1 ) = - ( ∆Hº_rxn / R ) ( 1 / T_2 - 1 / T_1 )