Chapter 14 Equilibrium

At elevated temperatures ammonium carbonate, NH₂COONH₄, is in equilibrium with NH₃ and CO₂ according to the equation;

NH₂COONH₄(s) ↔ 2 NH₃(g) + CO₂(g)

What is the equilibrium expression for this reaction?

• K = 2 [NH₃][CO₂]

  [NH₂COONH₄]

• K = [NH₃]²[CO₂]

  [NH₂COONH₄]

• K = 2 [NH₃][CO₂]

• K = [NH₃]²[CO₂]

Tags

NGSS.HS-PS1-6

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]  

Tags

NGSS.HS-PS1-6

For the following reaction: H₂(g) + Cl₂ (g) ↔ 2HCl(g), calculate the concentration of HCl when K_eq= 2.3x10^-5, [H₂]= 0.0056mol, [Cl₂]= 0.0048mol.

• 6.2 x 10^-10 M

• 2.5 x 10^-5 M

• 1.1 M

• 1.2 M

Tags

NGSS.HS-PS1-6

NGSS.HS-PS1-7

Consider the following reaction. What would be the equilibrium constant expression?

4Br₂(g) + CH₄(g) ↔ 4HBr(g) + CBr₄(g)

• [Br₂]⁴ [CH₄]

  [HBr]⁴ [CBr₄]

• [HBr]⁴ [CBr₄]

  [Br₂]⁴ [CH₄]

• [HBr ]

  [Br₂]⁴ [CH₄]

• [HBr]⁴ [CBr₄]

  [Br₂]⁴ [CH₄]⁴

Tags

NGSS.HS-PS1-7

What kind of equilibrium does the reaction below show?
CaCO_{3 (s)} ↔ CaO _(s) + CO_{2 (g)}

• Heterogeneous equilibrium, all the reactants and products are in the same physical state.
• Homogeneous equilibrium, all the reactants and products are in the same physical state.
• Heterogeneous equilibrium, the reactants and products are present in more than one physical state
• Homogeneous equilibrium, the reactants and products are present in more than one physical state

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.

Tags

NGSS.HS-PS1-6

Consider the following reaction :    
SO_{2 (g)} +  NO_{2 (g)} ↔ SO_{3 (g)} + NO (g)  
had reached a state of equilibrium, was found to contain   0.40 M SO₃ , 0.30 M NO, 0.15 M NO₂ , and 0.20 M SO₂. Calculate the equilibrium constant  for this reaction.

• 4
• .42
• .25
• 1

Tags

NGSS.HS-PS1-6

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

Tags

NGSS.HS-PS1-7

A large value of K_c indicates--

• more products than reactants at equilibrium

• more reactants than products at equlibrium

• reactants = products

• only products are present at equilibrium

• 9.47×10¹

• 3.2×10³

• 8.28×10^-2

• 2.45×10^-3