Oxidation of Elements Lesson

Chapter 16 Oxidation_Reduction

Multiple Choice

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

If the pressure in the system is increased,  which substance will increase in concentration?

• N₂
• H₂
• N₂ and H₂
• NH₃

Multiple Choice

What is the K_eq expression for this reaction?

2 NO_(g) + O_2(g) ⇌ 2 NO_2(g)

• K_eq = [NO₂]² / [NO]² [O₂]

• K_eq = [NO]² [O₂] / [NO₂]²

• K_eq = [NO]² [O₂] [NO₂]²

• K_eq = [NO₂]² / [NO]² + [O₂]

Multiple Choice

This symbol indicates that a reaction is ____________

• reversible
• irreversible

Multiple Choice

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]

Multiple Choice

At what time the reaction reached equilibrium?

• t₁
• t₂
• t₃
• t₄

Multiple Choice

For the reaction...
SO₂ + O₂ <−>  SO₃
If the equilibrium shifts to the right, the concentration of O₂ will ___________.

• increase
• decrease
• remain the same
• double

Multiple Choice

For the reaction...
SO₂ + O₂  <−>  SO₃
If the concentration of SO₂ is increased, the equilibrium of the reaction will shift ___________.

• left
• right
• left and right 
• neither left nor right

Multiple Choice

2A + 3B  <---->  2AB
The forward reaction forms the substance __________.

• A
• B
• AB
• A + B

Multiple Choice

Which of the following represents reduction?

• C →  CO
• N₂ →  NH₃
• Zn  →   Zn²⁺ 
• H₂ →  H₂O

Multiple Choice

Which of the following represents oxidation?

• C → CH₄

• Fe³⁺ → Fe²⁺

• Cl₂ → 2Cl^-

• Zn → ZnO

Multiple Choice

What is the oxidation number of nitrogen in N₂?

• -3

• 0

• +4

• -1

Multiple Choice

Reduction is the ___________ of electrons.

• loss

• gain

• sharing

• transfer

Multiple Choice

What is the oxidation number of chlorine in HClO?

• 0

• -1

• +1

• +5

Multiple Choice

What is the oxidation number of chlorine in HClO?

• 0

• -1

• +1

• +5

Multiple Choice

What is the reduction half-reaction for the following redox reaction?
                                           Zn + HgO $$\longrightarrow$$  ZnO + Hg

• Zn        $$\longrightarrow$$  Zn2+ 2e–

• Hg2+      +      2e–    $$\longrightarrow$$         Hg

• Zn    +    HgO

• ZnO     +     Hg

Multiple Choice

Which of the following reactions is balanced by both mass and charge?

• Fe⁺² + Al →Fe + Al⁺³
• Cu + Fe⁺² → Cu⁺¹ + Fe⁺³
• F₂ + Br^- --> F^- + Br₂
• Fe⁺² + 2 Cu --> 2 Cu⁺ + Fe

Multiple Choice

What coefficient would Fe⁺² have in the following reaction?

___ Al + ___ Fe⁺² → ___ Al⁺³ + ___ Fe

• 1

• 2

• 3

• 6

Multiple Choice

Which of the following is NOT a redox reaction?

• Displacement

• Decomposition

• Synthesis

• Neutralisation

• Combustion

Multiple Choice

In the reaction
2Ca(s) + O₂(g) --> 2CaO(s), calcium is __________

• Reduced
• Synthesized
• Oxidized
• None of the above

Multiple Choice

Which of the following half reactions correctly represents a reduction half reaction?

• Fe →Fe²⁺ + 2e^-
• Pb⁴⁺ + 2e^- →Pb²⁺
• 2O^-2 →O₂ + 4e^-
• Fe + 3e^- →Fe³⁺

Multiple Choice

Which statement is true:
Mg → Mg²⁺ + 2e^–

• Mg gains 2 electrons
• Mg_²⁺ loses 2 electrons
• Mg loses 1 electron
• Mg loses 2 electrons

Multiple Choice

In the reaction
2Ca(s) + O₂(g) --> 2CaO(s), calcium is __________

• Reduced
• Synthesized
• Oxidized
• None of the above

Multiple Choice

Oxygen always has an oxidation number of...

• -1

• 1

• 2

• -2

Multiple Choice

Oxygen always has an oxidation number of...

• -1

• 1

• 2

• -2