HW4_Solutions

# HW4_Solutions - estrada(gse77 – Homework 4 – Sutcliffe...

This preview shows pages 1–3. Sign up to view the full content.

This preview has intentionally blurred sections. Sign up to view the full version.

View Full Document
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: estrada (gse77) – Homework 4 – Sutcliffe – (52410) 1 This print-out should have 21 questions. Multiple-choice questions may continue on the next column or page – find all choices before answering. 001 10.0 points When the chemical reaction A + B ⇀ ↽ C + D is at equilibrium, 1. neither the forward nor the reverse reac- tions have stopped. correct 2. both the forward and reverse reactions have stopped. 3. the reverse reaction has stopped. 4. the forward reaction has stopped. 5. the sum of the concentrations of A and B equals the sum of the concentrations of C and D. 6. all four concentrations are equal. Explanation: Chemical equilibrium is dynamic equilib- rium, with both foward and reverse processes occuring at the same rate. 002 10.0 points What is the equilibrium expression for the following equation? Assume that all species here are gases. A + 3 B ⇀ ↽ 2 C + D 1. [A] [B] 3 [C] 2 [D] 2. 2 [C] [D] 3 [A] [B] 3. [C] 2 [D] [A] [B] 3 correct 4. 3 [A] [B] 2 [C] [D] Explanation: Equilibrium expressions are written with the products (raised to the powers of their co- efficients) in the numerator and the reactants (raised to the powers of their coefficients) in the denominator. 003 10.0 points What is the form of the equilibrium constant for the process PbO(s) + CO 2 (g) ⇀ ↽ PbCO 3 (s) ? P species means the pressure of species. 1. K p = [PbCO 3 ] [PbO] P CO 2 2. K p = P PbCO 3 P CO 2 3. No other choice is correct. 4. K c = [PbCO 3 ] 2 [CO 2 ] [PbO] 5. K p = 1 P CO 2 correct Explanation: Solids are not included in the K expression. 004 10.0 points Consider the following reactions at 25 ◦ C: reaction K c 2 NO(g) ⇀ ↽ N 2 (g) + O 2 (g) 1 × 10 30 2 H 2 O(g) ⇀ ↽ 2 H 2 (g) + O 2 (g) 5 × 10 − 82 2 CO(g) + O 2 (g) ⇀ ↽ 2 CO 2 (g) 3 × 10 91 Which compound is most likely to dissociate and give O 2 (g) at 25 ◦ C? 1. CO 2. CO 2 3. H 2 O 4. NO correct Explanation: Only two are dissociation reactions: disso- ciation of NO and dissociation of H 2 O. K c is greater for dissociation of NO. estrada (gse77) – Homework 4 – Sutcliffe – (52410) 2 005 10.0 points The equilibrium constant for the reaction 4 NH 3 (g) + 5 O 2 (g) → 4 NO(g) + 6 H 2 O(g) is K . Calculate the equilibrium constant for the reaction 2 NO(g) + 3 H 2 O(g) → 2 NH 3 (g) + 5 2 O 2 (g) . 1.- 2 K 2. 1 √ K correct 3.- K 2 4. 1 K 5.- K Explanation: 006 10.0 points If the equilibrium constant for the reaction Ni(s) + 4 CO(g) → Ni(CO) 4 (g) is 2.72 at a certain temperature, what is the equilibrium constant for the reaction Ni(CO) 4 (g) → Ni(s) + 4 CO(g) at the same temperature? 1. 5.44 2. 1.36 3. 2.72 4. 0.368 correct Explanation: 007 10.0 points Consider the reaction NH 4 (NH 2 CO 2 )(s) → 2 NH 3 (g) + CO 2 (g) ....
View Full Document

{[ snackBarMessage ]}

### Page1 / 7

HW4_Solutions - estrada(gse77 – Homework 4 – Sutcliffe...

This preview shows document pages 1 - 3. Sign up to view the full document.

View Full Document
Ask a homework question - tutors are online