Question

is built in the "Test Form"box under Banner ID number 1. Nitrogen dioxide was added to a reaction vessel reacts according to the reaction below. At brium, the concentration of NO, was determined to be 0.42 M and the concentration of NO was determined to be 0.039 M What is the concentration based equilibrium constant, Ke? 2 NO, (S NO. 0.18 b0016 0.22 4.5 .7.5 x 10' and 4.8 x 10-"). 2. The different K's for H.PO, not in any specific order, are 6.2 x 10 List them in order for Kel. K and Kal. K -6.2 x 10", K -7.5 x 10 and K. - 4.8 x 10" hk-7.5 x 10K -62 x 10"and K = 4.8 x 10" K -48x10-), K -6.2 x 10 and ke-7.5 x 10 d. Ke-7.5 x 10'. -4.8 x 10-13 and ke-6.2 x 10* Fill in bubble "e" in the "Test Form" box under Banner ID number. 3. When a system is in equilibrium, a. the products are in higher concentration than the reactants. b. the reactants are in higher concentration than the products. c. the reaction is going from left to right at the same rate the reaction is going from right to left. d. the concentration of the reactants and products are changing. 4. Determine the change in entropy when 14.6 grams of oxygen react with ethanol. (Hint: use stoichiometry.) CHOH () + 3 02 (g) - 2 CO2 (g) + 3 H20 (1) AS=-139 J/mol K a.-2030 J/K b. -63.4 J/K c. -21.1 JAK d. -42.3 J/K 5. Gibb's energy a is negative when a chemical reaction is favorable from left to right. b. is positive when a chemical reaction is favorable from left to right. c. can never be negative. d. can never be positive.

Answer 1

1.

For the given reaction

K_c = $\frac{[N_2O_4]}{[NO_2]^{2}}$ =  $\frac{(0.039)}{(0.42)^{2}}$ = 0.22.

2.

First dissociation constant is highest and third dissocistion constant is lowest.

Ka₁ = 7.5×10^-3, Ka₂ = 6.2×10^-8 , Ka₃ = 4.8×10^-13

3.

When a system is equilibrium

The rate forward and reverse reaction is equal.

Hence option c is correct.

4.

Entropy change when 3 mol oxygen reacted = -139 J.

Or, entropy change when 1 mol oxygen reacted = - (139/3) J

Now, moles of oxygen = (14.6/32) = 0.456

Then entropy change = - (139× 0.456 )/3 = - 21.1 J.

5.

Gibb's energy is negative when a chemical reaction is favourable from left (reactant) to right (product) .