CHM 112 Final Exam Review (Unit 7-9)

Define chemical equilibrium.

• A reaction is reversible.
• The concentration of the reactants is equal to the concentration of the products.
• The rate of a forward reaction is equal to the rate of the reverse reaction.
• The reaction stops and no further change in concentration occurs.

2NH₃+22kJ↔N₂+3H₂
Which direction does the reaction shift if NH₃ was added?

• Shift right 
• Shift left
• No shift
• Shift both directions

For the reaction...
N_{2 (g)} +  3 H_2 (g) <−> 2 NH_{3 (g)}

If the pressure in the system is increased, the reaction will __________________.

•  shift to the left
• shift to the right
• not shift

What is the equilibrium-constant expression for 
CO₂(g) + H₂(g) ↔ CO(g) + H₂O(l)

• K_c= [CO][H₂O] / [CO₂][H₂]  
• K_c= [CO₂][H₂] / [CO]
• K_c= [CO₂][H₂] / [CO][H₂O]
• K_c= [CO] / [CO₂][H₂]  

For a given reaction, N₂ + 3H₂ --> 2NH₃. 1.0 M of N₂ is added to 2.0 M H₂. Once equilibrium has been established, it is found the molarity of NH₃ is 0.25M. What is the equilibrium concentration of N₂ and H₂?

• [N₂] = 0.875 M, [H₂ ]= 1.625

• [N₂] = 0.85 M, [H₂ ]= 0.75

• [N₂] = 0.75 M, [H₂ ]= 1.875

• [N₂] = 0.5 M, [H₂ ]= 0.125

Silver chromate, Ag₂CrO₄, has a K_sp of 8.96 x 10^-12. Calculate the solubility in g/L of silver chromate.

• 1.31 x 10^-4

• 0.0435

• 0.00685

• 0.362

The solubility of silver(I) carbonate is 3.6 × 10^–2 g/L. What is the solubility product constant for silver(I) carbonate?

• 4.4x10^-15

• 8.2x10^-12

• 1.7x10^-8

• 1.3x10^-4

Ksp for CaF₂ is 3.9x10^-11 mol/L. If 50 mL of 0.025 M CaBr₂ is mixed with 40 mL of 0.030 M NaF, will a precipitate occur?

• Yes, Q = 9.9x10^-6

• Yes, Q = 9.8x10^-5

• Yes Q = 1.85x10^-3

• No, Q = 4.6x10^-12

When dissolved in water, acids produce:

• bases
• salts
• hydrogen ions
• hydroxide ions

In this rxn: HBr + NH₃ --> NH₄⁺ + Br^- the acid and its conjugate base, respectively are...

• NH₃ and NH₄⁺

• NH₃ and Br^-

• HBr and NH₄⁺

• HBr and Br^-