Question 1

Choose the correct equilibrium constant expression for the equilibrium 
H2(g)+ I2(g)   2 HI(g)

Accepted Answer

A) K =   
B) K =   
C) K =   
D) K =   
E) K =   
A) K =   
B) K =   
C) K =   
D) K =   
E) K =

Question 2

Consider the particulate level representation of a reaction of the form:     Based on just this diagram,which of the following does not correctly describes this reaction?

Accepted Answer

A) The collision was ineffective. 
B) Product did not form. 
C) The orientation of the reactants to with respect to each other was wrong. 
D) The molecules had too much potential energy. 
E) All of the above do describe this reaction. 
A) The collision was ineffective. 
B) Product did not form. 
C) The orientation of the reactants to with respect to each other was wrong. 
D) The molecules had too much potential energy. 
E) All of the above do describe this reaction.

Question 3

Choose the correct equilibrium constant expression for the equilibrium 
2 H2(g)+ O2(g)   2 H2O(   ).

Accepted Answer

A) K =   
B) K =   
C) K =   
D) K =   
E) K =   
A) K =   
B) K =   
C) K =   
D) K =   
E) K =

Question 4

Calculate the molar solubility of aluminum phosphate in water given that Ksp = 1.3 × 10-20.

Accepted Answer

A) 1.1 × 10-10 M 
B) 1.5 × 10-7 M 
C) 1.7 × 10-40 M 
D) 5.9 × 1039 M 
E) 7.7 × 1019 M 
A) 1.1 × 10-10 M 
B) 1.5 × 10-7 M 
C) 1.7 × 10-40 M 
D) 5.9 × 1039 M 
E) 7.7 × 1019 M

Question 5

Which of the following statements is/are correct?
i.An object hanging motionless on a spring is in a static equilibrium
ii.In a dynamic equilibrium,the reversible changes occur continuously,even though there is no appearance of change
iii.The amounts of substances present in a system at equilibrium are equal

Accepted Answer

A) i only 
B) ii only 
C) iii only 
D) i and ii 
E) ii and iii 
A) i only 
B) ii only 
C) iii only 
D) i and ii 
E) ii and iii

Question 6

Which of the following statements is/are correct?
i.If an equilibrium constant is very large,the reverse reaction is favored
ii.If an equilibrium constant is very small,the forward reaction is favored
iii.If an equilibrium constant is neither large nor small,appreciable quantities of all species are present at equilibrium

Accepted Answer

A) iii only 
B) i and ii 
C) ii and iii 
D) All statements are incorrect 
E) All statements are correct 
A) iii only 
B) i and ii 
C) ii and iii 
D) All statements are incorrect 
E) All statements are correct

Question 7

Which of the following is the best description of the activation energy for the forward reaction for the reaction A2 + B2   2 AB?

Accepted Answer

A) The difference between the energy of the activated complex and the reactant energies 
B) The difference between the product energies and the energy of the activated complex 
C) The difference between the product energies and the reactant energies 
D) The sum of the energy of the activated complex and the reactant energies 
E) The sum of the energy of the activated complex and the product energies 
A) The difference between the energy of the activated complex and the reactant energies 
B) The difference between the product energies and the energy of the activated complex 
C) The difference between the product energies and the reactant energies 
D) The sum of the energy of the activated complex and the reactant energies 
E) The sum of the energy of the activated complex and the product energies

Question 8

If a reaction is carried out in an aqueous solution,which of the following changes would not affect the rate of the reaction?

Accepted Answer

A) Increasing the temperature 
B) Changing the concentration of reactants 
C) Increasing the size of the reaction vessel 
D) Adding a catalyst 
E) More than one would not affect the rate of the reaction 
A) Increasing the temperature 
B) Changing the concentration of reactants 
C) Increasing the size of the reaction vessel 
D) Adding a catalyst 
E) More than one would not affect the rate of the reaction

Question 9

Consider the diagram given below.   Which number point on the diagram indicates the Ea for the forward reaction?

Accepted Answer

A) 1 
B) 2 
C) 3 
D) 4 
E) 5 
A) 1 
B) 2 
C) 3 
D) 4 
E) 5

Question 10

K = 1.3 × 10-10 for the reaction HC6H5O(aq)   H+(aq)+ C6H5O-(aq).In which direction is the equilibrium favored?

Accepted Answer

A) Forward 
B) Reverse 
C) Appreciable quantities of all species are present at equilibrium 
D) No direction is favored 
E) There is not enough information to determine the direction 
A) Forward 
B) Reverse 
C) Appreciable quantities of all species are present at equilibrium 
D) No direction is favored 
E) There is not enough information to determine the direction

Question 11

Which of the following statements is incorrect?
i.The collision theory of chemical reactions states that what we see as a chemical reaction is the overall effect of a high number of individual collisions between reacting particles
ii.A violent,bond-breaking collision is most apt to occur if the colliding molecules are moving at high speed
iii.Most collisions do not result in a reaction

Accepted Answer

A) iii only 
B) i and iii 
C) ii and iii 
D) All statements are correct 
E) All statements are incorrect 
A) iii only 
B) i and iii 
C) ii and iii 
D) All statements are correct 
E) All statements are incorrect

Question 12

Ka = 1.8 × 10-5 for the ionization of HC2H3O2(aq).Determine the [HC2H3O2]/[C2H3O2-] ratio that will produce a buffer at pH = 5.00.

Accepted Answer

A) 3.6 × 10-6 
B) 9.0 × 10-5 
C) 0.18 
D) 0.56 
E) 1.8 
A) 3.6 × 10-6 
B) 9.0 × 10-5 
C) 0.18 
D) 0.56 
E) 1.8

Question 13

How does increasing the temperature increase the rate of a chemical reaction?

Accepted Answer

A) The fraction of sample with the minimum kinetic energy required to react is increased 
B) The activation energy for the reaction is decreased 
C) The bond energy of the reactants is decreased 
D) The likelihood that molecules and ions will have the required geometry is increased 
E) The electrons become more reactive because they spin on their own axes at a higher rate 
A) The fraction of sample with the minimum kinetic energy required to react is increased 
B) The activation energy for the reaction is decreased 
C) The bond energy of the reactants is decreased 
D) The likelihood that molecules and ions will have the required geometry is increased 
E) The electrons become more reactive because they spin on their own axes at a higher rate

Question 14

Which of the following statements are incorrect?
i.When opposing reversible reactions occur at different rates,the faster reaction gradually becomes slower.ii.Equilibrium is established when forward and reverse reaction rates become equal
iii.In the development of a chemical equilibrium,the reverse reaction rate decreases over time until equilibrium is established

Accepted Answer

A) iii only 
B) i and ii 
C) i and iii 
D) ii and iii 
E) i, ii, and iii 
A) iii only 
B) i and ii 
C) i and iii 
D) ii and iii 
E) i, ii, and iii

Question 15

A molecular collision is sufficiently energetic to cause a reaction,yet no reaction occurs.Which of the following is the least likely explanation?

Accepted Answer

A) The proton-proton interaction is too large 
B) The molecules have poor orientation 
C) One of the molecules is not moving too slowly. 
D) One or both the molecules does not have enough energy. 
E) All of the above could be an explanation. 
A) The proton-proton interaction is too large 
B) The molecules have poor orientation 
C) One of the molecules is not moving too slowly. 
D) One or both the molecules does not have enough energy. 
E) All of the above could be an explanation.

Question 16

Predict what will happen if the partial pressure of nitrogen is increased after the reaction N2(g)+ 3 H2(g)   2 NH3(g)has reached equilibrium.

Accepted Answer

A) The position of equilibrium will shift to the left 
B) The molar concentration of H2 will increase 
C) The partial pressure of H2 will increase 
D) The concentration of NH3 will decrease 
E) More ammonia will form 
A) The position of equilibrium will shift to the left 
B) The molar concentration of H2 will increase 
C) The partial pressure of H2 will increase 
D) The concentration of NH3 will decrease 
E) More ammonia will form

Question 17

What will happen if the temperature is increased after equilibrium has been established in the reaction shown? 
2 Cl2(g)+ 2 H2O(g)+ 113 kJ   4 HCl(g)+ O2(g)

Accepted Answer

A) The position of equilibrium shifts to the left 
B) More HCl will form 
C) More Cl2 will form 
D) The partial pressure of oxygen will decrease 
E) The concentration of H2O will increase 
A) The position of equilibrium shifts to the left 
B) More HCl will form 
C) More Cl2 will form 
D) The partial pressure of oxygen will decrease 
E) The concentration of H2O will increase

Question 18

Consider the following reaction coordinate diagram.   Based on this diagram,which of the following is correct?

Accepted Answer

A) 2 represents ΔE and the reaction is exothermic. 
B) 2 represents ΔE and the reaction is endothermic 
C) 3 represents ΔE and the reaction is endothermic 
D) 3 represents ΔE and the reaction is exothermic 
E) 5 represents ΔE and the reaction is exothermic 
A) 2 represents ΔE and the reaction is exothermic. 
B) 2 represents ΔE and the reaction is endothermic 
C) 3 represents ΔE and the reaction is endothermic 
D) 3 represents ΔE and the reaction is exothermic 
E) 5 represents ΔE and the reaction is exothermic

Question 19

Choose the correct equilibrium constant expression for the equilibrium 
4 NO(g)+ 6 H2O(g)   4 NH3(g)+ 5 O2(g)

Accepted Answer

A) K =   
B) K =   
C) K =   
D) K =   
E) K =   
A) K =   
B) K =   
C) K =   
D) K =   
E) K =

Question 20

If a copper(II)nitrate solution is added to a sodium sulfide solution the following equilibrium will be attained: Cu2+(aq)+ S2-(aq)   CuS(s).For this equilibrium,K = 6.3 × 1047.Choose the correct equilibrium constant expression and the correct direction favored at equilibrium.

Accepted Answer

A) K =   forward 
B) K =   reverse 
C) K =   forward 
D) K =   reverse 
E) K =   appreciable quantities of all species are present at equilibrium 
A) K =   forward 
B) K =   reverse 
C) K =   forward 
D) K =   reverse 
E) K =   appreciable quantities of all species are present at equilibrium

Choose the correct equilibrium constant expression for the equilibrium H₂(g)+ I₂(g) 2 HI(g)

Consider the particulate level representation of a reaction of the form: Based on just this diagram,which of the following does not correctly describes this reaction?

Choose the correct equilibrium constant expression for the equilibrium 2 H₂(g)+ O₂(g) 2 H₂O( ).

Calculate the molar solubility of aluminum phosphate in water given that K_sp = 1.3 × 10^-20.

Which of the following is the best description of the activation energy for the forward reaction for the reaction A₂ + B₂ 2 AB?

If a reaction is carried out in an aqueous solution,which of the following changes would not affect the rate of the reaction?

Consider the diagram given below. Which number point on the diagram indicates the E_a for the forward reaction?

K = 1.3 × 10^-10 for the reaction HC₆H₅O(aq) H⁺(aq)+ C₆H₅O^-(aq).In which direction is the equilibrium favored?

K_a = 1.8 × 10^-5 for the ionization of HC₂H₃O₂(aq).Determine the [HC₂H₃O₂]/[C₂H₃O₂^-] ratio that will produce a buffer at pH = 5.00.

How does increasing the temperature increase the rate of a chemical reaction?

A molecular collision is sufficiently energetic to cause a reaction,yet no reaction occurs.Which of the following is the least likely explanation?

Predict what will happen if the partial pressure of nitrogen is increased after the reaction N₂(g)+ 3 H₂(g) 2 NH₃(g)has reached equilibrium.

What will happen if the temperature is increased after equilibrium has been established in the reaction shown? 2 Cl₂(g)+ 2 H₂O(g)+ 113 kJ 4 HCl(g)+ O₂(g)

Consider the following reaction coordinate diagram. Based on this diagram,which of the following is correct?

Choose the correct equilibrium constant expression for the equilibrium 4 NO(g)+ 6 H₂O(g) 4 NH₃(g)+ 5 O₂(g)

If a copper(II)nitrate solution is added to a sodium sulfide solution the following equilibrium will be attained: Cu²⁺(aq)+ S^2-(aq) CuS(s).For this equilibrium,K = 6.3 × 10⁴⁷.Choose the correct equilibrium constant expression and the correct direction favored at equilibrium.

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Introduction to Gases

Atomic Theory: The Nuclear Model of the Atom

Chemical Nomenclature

Chemical Formula Relationships

Chemical Reactions

Chemical Change

Quantity Relationships in Chemical Reactions

Atomic Theory: The Quantum Model of the Atom

Chemical Bonding

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Exam 18: Chemical Equilibrium

Choose the correct equilibrium constant expression for the equilibrium H2(g)+ I2(g) 2 HI(g)

Consider the particulate level representation of a reaction of the form: Based on just this diagram,which of the following does not correctly describes this reaction?

Choose the correct equilibrium constant expression for the equilibrium 2 H2(g)+ O2(g) 2 H2O( ).

Calculate the molar solubility of aluminum phosphate in water given that Ksp = 1.3 × 10-20.

Which of the following is the best description of the activation energy for the forward reaction for the reaction A2 + B2 2 AB?

If a reaction is carried out in an aqueous solution,which of the following changes would not affect the rate of the reaction?

Consider the diagram given below. Which number point on the diagram indicates the Ea for the forward reaction?

K = 1.3 × 10-10 for the reaction HC6H5O(aq) H+(aq)+ C6H5O-(aq).In which direction is the equilibrium favored?

Ka = 1.8 × 10-5 for the ionization of HC2H3O2(aq).Determine the [HC2H3O2]/[C2H3O2-] ratio that will produce a buffer at pH = 5.00.

How does increasing the temperature increase the rate of a chemical reaction?

A molecular collision is sufficiently energetic to cause a reaction,yet no reaction occurs.Which of the following is the least likely explanation?

Predict what will happen if the partial pressure of nitrogen is increased after the reaction N2(g)+ 3 H2(g) 2 NH3(g)has reached equilibrium.

What will happen if the temperature is increased after equilibrium has been established in the reaction shown? 2 Cl2(g)+ 2 H2O(g)+ 113 kJ 4 HCl(g)+ O2(g)

Consider the following reaction coordinate diagram. Based on this diagram,which of the following is correct?

Choose the correct equilibrium constant expression for the equilibrium 4 NO(g)+ 6 H2O(g) 4 NH3(g)+ 5 O2(g)

If a copper(II)nitrate solution is added to a sodium sulfide solution the following equilibrium will be attained: Cu2+(aq)+ S2-(aq) CuS(s).For this equilibrium,K = 6.3 × 1047.Choose the correct equilibrium constant expression and the correct direction favored at equilibrium.

Matter and Energy

Measurement and Chemical Calculations

Introduction to Gases

Atomic Theory: The Nuclear Model of the Atom

Chemical Nomenclature

Chemical Formula Relationships

Chemical Reactions

Chemical Change

Quantity Relationships in Chemical Reactions

Atomic Theory: The Quantum Model of the Atom

Chemical Bonding

Structure and Shape

The Ideal Gas Law and Its Applications

Gases, Liquids, and Solids

Solutions

Acidbase Proton Transferreactions

Oxidationreduction Electron Transferreactions

Nuclear Chemistry

Organic Chemistry

Biochemistry

Filters

Choose the correct equilibrium constant expression for the equilibrium H₂(g)+ I₂(g) 2 HI(g)

Choose the correct equilibrium constant expression for the equilibrium 2 H₂(g)+ O₂(g) 2 H₂O( ).

Calculate the molar solubility of aluminum phosphate in water given that K_sp = 1.3 × 10^-20.

Which of the following is the best description of the activation energy for the forward reaction for the reaction A₂ + B₂ 2 AB?

Consider the diagram given below. Which number point on the diagram indicates the E_a for the forward reaction?

K = 1.3 × 10^-10 for the reaction HC₆H₅O(aq) H⁺(aq)+ C₆H₅O^-(aq).In which direction is the equilibrium favored?

K_a = 1.8 × 10^-5 for the ionization of HC₂H₃O₂(aq).Determine the [HC₂H₃O₂]/[C₂H₃O₂^-] ratio that will produce a buffer at pH = 5.00.

Predict what will happen if the partial pressure of nitrogen is increased after the reaction N₂(g)+ 3 H₂(g) 2 NH₃(g)has reached equilibrium.

What will happen if the temperature is increased after equilibrium has been established in the reaction shown? 2 Cl₂(g)+ 2 H₂O(g)+ 113 kJ 4 HCl(g)+ O₂(g)

Choose the correct equilibrium constant expression for the equilibrium 4 NO(g)+ 6 H₂O(g) 4 NH₃(g)+ 5 O₂(g)

If a copper(II)nitrate solution is added to a sodium sulfide solution the following equilibrium will be attained: Cu²⁺(aq)+ S^2-(aq) CuS(s).For this equilibrium,K = 6.3 × 10⁴⁷.Choose the correct equilibrium constant expression and the correct direction favored at equilibrium.