Question 1

Given: PH₃(g)$\rightarrow$ P₄(s),basic solution. How many electrons appear in the balanced half-reaction?

Accepted Answer

In the balanced half-reaction for the conversion of PH3 to P4 in a basic solution, each phosphorus atom in PH3 loses 3 electrons to form P4. Since there are 4 phosphorus atoms in P4, a total of 12 electrons are involved (4 phosphorus atoms x 3 electrons each).

Question 2

The standard potential of the Cu²⁺/Cu electrode is +0.34 V and the standard potential of the cell Ag(s)|AgCl(s)|Cl^-(aq)m Cu²⁺(aq)|Cu(s) Is +0.12 V.What is the standard potential of the AgCl/Ag,Cl^- electrode?

Accepted Answer

The standard cell potential is the difference between the standard potentials of the two half-cells. Given the cell potential is +0.12 V and the Cu²⁺/Cu potential is +0.34 V, the AgCl/Ag, Cl⁻ potential is calculated as +0.12 V - (+0.34 V) = -0.22 V. However, the correct sign for the AgCl/Ag, Cl⁻ electrode is +0.22 V, considering the direction of the cell reaction.

Question 3

When equilibrium is reached in an electrochemical cell,the voltage reaches its maximum value.

Accepted Answer

At equilibrium, the cell voltage is zero because the forward and reverse reactions occur at the same rate, resulting in no net electron flow.

Question 4

A cell that uses bromine to oxidize chloride ion under standard conditions at 298 K has a positive potential.True or false?

Accepted Answer

The answer of A cell that uses bromine to oxidize...

Question 5

When the Ag(s)|AgCl(s)|Cl^-(aq)electrode acts as a cathode,the reaction is

Accepted Answer

The half-cell reaction given for the Ag(s)F1F1F1S1F1F1F10AgCl(s)F1F1F1S1F1F1F10ClF1F1F1S1^F1F1F10 electrode acting as a cathode is: AgCl(s)+ eF1F1F1S1^F1F1F10 F1F1F1S1F1F1F10 Ag(s)+ ClF1F1F1S1^F1F1F10(aq) This means that AgCl(s) gains an electron to become Ag(s) while ClF1F1F1S1^F1F1F10 is released into the solution. Therefore, choice E is the best choice.

Question 6

In the determination of iron in vitamins,Fe²⁺ is titrated with permanganate,MnO₄^-,in acidic solution.The products of the reaction are Fe³⁺ and Mn²⁺.In the balanced equation,the number of electrons transferred is

Accepted Answer

In the balanced redox reaction, 5 electrons are transferred from Fe²⁺ to MnO₄⁻. Fe²⁺ is oxidized to Fe³⁺ (losing 1 electron), and MnO₄⁻ is reduced to Mn²⁺ (gaining 5 electrons).

Question 7

Given: N₂H₅⁺(aq)$\rightarrow$ N₂(g). How many electrons appear in the balanced half-reaction?

Accepted Answer

The given reaction is a shorthand for a redox reaction involving uranium. The uranium goes from an oxidation state of +6 in UO2^2+ (implied by "B12" for uranium and "B0" for oxygen in a compound, with "S1U1" indicating one uranium atom and "B15" and "B0" indicating the presence of hydrogen and oxygen in water, respectively) to an oxidation state of +4 in UO2 (implied by "B12" for uranium and "B0" for oxygen in a gas). This change represents a reduction of uranium by 2 oxidation states, requiring 2 electrons per uranium atom. However, the notation suggests this process involves two uranium atoms (implied by the stoichiometry of the reactants and products), thus a total of 4 electrons are involved in the balanced half-reaction.

Question 8

The standard potential of the Cu²⁺/Cu electrode is +0.34 V and the standard potential of the cell Pb(s)|Pb²⁺(aq)m Cu²⁺(aq)|Cu(s) Is +0.47 V.What is the standard potential of the Pb²⁺/Pb electrode?

Accepted Answer

The answer of The standard potential of the Cu²⁺/Cu electrode...

Question 9

If the standard potentials for the couples Cu²⁺/Cu,Ag⁺/Ag,and Fe²⁺/Fe are +0.34,+0.80,and -0.44 V,respectively,which is the strongest reducing agent?

Accepted Answer

The answer of If the standard potentials for the couples...

Question 10

What is the proper cell diagram for the reaction 2AgCl(s)+ H₂(g)$\rightarrow$ 2Ag(s)+ 2H⁺(aq)+ 2Cl^-(aq)

Accepted Answer

The anode is the site of oxidation, and the cathode is the site of reduction. In this reaction, 2AgCl(s) is being reduced to 2Ag(s), so the cathode will involve silver ions. The reactant H₂(g) is being oxidized to form H⁺(aq), so the anode will involve hydrogen ions. Therefore, in the anode chamber, H+ ions will react with Cl- ions to form HCl, and in the cathode chamber, Ag+ ions will react with electrons to form Ag(s). The Pt electrode will be present in both chambers as a conductor. Thus, the proper cell diagram is Pt | H2(g,1 atm) | HCl(aq) || AgCl(s) | Ag(s) | Pt. Statement B is the only one that fits this description.

Question 11

Given: S₂O₄²^-(aq)$\rightarrow$ SO₃²^-(aq),basic solution. How many electrons appear in the balanced half-reaction?

Accepted Answer

In the balanced half-reaction for the reduction of dithionite ion (S₂O₄²⁻) to sulfite ion (SO₃²⁻) in a basic solution, two electrons are transferred.

Question 12

A cell that uses bromine to oxidize hydrogen to H⁺ under standard conditions at 298 K has a negative potential?

Accepted Answer

Under standard conditions, the cell potential for the reaction where bromine oxidizes hydrogen to H⁺ is positive, as bromine is a strong oxidizing agent and hydrogen is a reducing agent.

Question 13

When a sample of an unknown metal is dropped into 1 M H⁺(aq)under standard conditions,bubbles are observed.The unknown metal could be silver.

Accepted Answer

The given chemical equation indicates that the solution contains sulfuric acid and hydrogen peroxide. The production of bubbles when the unknown metal is dropped suggests a chemical reaction with the solution, but it doesn't provide enough evidence to identify the metal as silver.

Question 14

Given: Zn(s)+ OH^-(aq)+ H₂O(l)+ NO₃^-(aq)$\rightarrow$ Zn(OH)₄²^-(aq)+ NH₃(g) If the coefficient of NO₃^- in the balanced equation is 1,how many electrons are transferred in the reaction?

Accepted Answer

The answer of Given: Zn(s)+ OH^-(aq)+ H₂O(l)+ NO₃^-(aq)$\rightarrow$ Zn(OH)₄²^-(aq)+...

Question 15

In a working electrochemical cell (+ cell voltage),the cations in the salt bridge move toward the cathode.

Accepted Answer

In a working electrochemical cell, the cations in the salt bridge move towards the cathode. This is because the cathode is negatively charged and therefore attracts the positively charged cations in the salt bridge. This movement of cations helps to maintain the electrical neutrality in both half-cells of the cell.

Question 16

How many electrons appear in the balanced half reaction: NO₃^-(aq)F$\rightarrow$ NO(g),in acidic solution?

Accepted Answer

The balanced half reaction for the reduction of NO to NO(g) in acidic solution is:
NO3- + 4H+ + 3e- → NO(g) + 2H2O
There are 3 electrons on the left side of the equation and 3 electrons on the right side, so the answer is 3.

Question 17

Given: Cr(OH)₃(s)$\rightarrow$ CrO₄²^-(aq),basic solution. How many electrons appear in the balanced half-reaction?

Accepted Answer

In the balanced half-reaction for the oxidation of Cr(OH)₃ to CrO₄²⁻ in a basic solution, Cr goes from an oxidation state of +3 to +6, which involves the loss of 3 electrons.

Question 18

In a working electrochemical cell (+ cell voltage),the electrons flow from the anode through the external circuit to the cathode.

Accepted Answer

In an electrochemical cell, the anode is negatively charged and the cathode is positively charged. Electrons flow from the anode (negative terminal) through the external circuit to the cathode (positive terminal) to balance the charge. This electron flow generates an electrical current, which produces the cell voltage. So, the statement is true.

Question 19

If the standard potentials for the couples Fe³⁺/Fe²⁺,MnO₄2^-0,H⁺/Mn²⁺,H₂O,Zn²⁺/Zn,V³⁺/V²⁺,and Br₂/Br^- are +0.77,+1.51,-0.76,-0.26,and +1.09 V,respectively,which is the strongest oxidizing agent?

Accepted Answer

The strongest oxidizing agent is the one with the highest standard reduction potential. MnO₄⁻ has the highest potential of +1.51 V, making it the strongest oxidizing agent among the given options.

Question 20

For the cell diagram Pt|H₂(g),H⁺(aq)m Cu²⁺(aq)|Cu(s) Which reaction occurs at the anode?

Accepted Answer

The answer of For the cell diagram Pt|H₂(g),H⁺(aq)m Cu²⁺(aq)|Cu(s) Which reaction...

Quiz 14: Electrochemistry

Given: PH₃(g) $\rightarrow$ P₄(s) ,basic solution. How many electrons appear in the balanced half-reaction?

The standard potential of the Cu²⁺/Cu electrode is +0.34 V and the standard potential of the cell Ag(s) |AgCl(s) |Cl^-(aq) m Cu²⁺(aq) |Cu(s) Is +0.12 V.What is the standard potential of the AgCl/Ag,Cl^- electrode?

When equilibrium is reached in an electrochemical cell,the voltage reaches its maximum value.

A cell that uses bromine to oxidize chloride ion under standard conditions at 298 K has a positive potential.True or false?

When the Ag(s) |AgCl(s) |Cl^-(aq) electrode acts as a cathode,the reaction is

In the determination of iron in vitamins,Fe²⁺ is titrated with permanganate,MnO₄^-,in acidic solution.The products of the reaction are Fe³⁺ and Mn²⁺.In the balanced equation,the number of electrons transferred is

Given: N₂H₅⁺(aq) $\rightarrow$ N₂(g) . How many electrons appear in the balanced half-reaction?

The standard potential of the Cu²⁺/Cu electrode is +0.34 V and the standard potential of the cell Pb(s) |Pb²⁺(aq) m Cu²⁺(aq) |Cu(s) Is +0.47 V.What is the standard potential of the Pb²⁺/Pb electrode?

If the standard potentials for the couples Cu²⁺/Cu,Ag⁺/Ag,and Fe²⁺/Fe are +0.34,+0.80,and -0.44 V,respectively,which is the strongest reducing agent?

What is the proper cell diagram for the reaction 2AgCl(s) + H₂(g) $\rightarrow$ 2Ag(s) + 2H⁺(aq) + 2Cl^-(aq)

Given: S₂O₄²^-(aq) $\rightarrow$ SO₃²^-(aq) ,basic solution. How many electrons appear in the balanced half-reaction?

A cell that uses bromine to oxidize hydrogen to H⁺ under standard conditions at 298 K has a negative potential?

When a sample of an unknown metal is dropped into 1 M H⁺(aq)under standard conditions,bubbles are observed.The unknown metal could be silver.

Given: Zn(s) + OH^-(aq) + H₂O(l) + NO₃^-(aq) $\rightarrow$ Zn(OH) ₄²^-(aq) + NH₃(g) If the coefficient of NO₃^- in the balanced equation is 1,how many electrons are transferred in the reaction?

In a working electrochemical cell (+ cell voltage),the cations in the salt bridge move toward the cathode.

How many electrons appear in the balanced half reaction: NO₃^-(aq) F $\rightarrow$ NO(g) ,in acidic solution?

Given: Cr(OH) ₃(s) $\rightarrow$ CrO₄²^-(aq) ,basic solution. How many electrons appear in the balanced half-reaction?

In a working electrochemical cell (+ cell voltage),the electrons flow from the anode through the external circuit to the cathode.

If the standard potentials for the couples Fe³⁺/Fe²⁺,MnO₄2^-0,H⁺/Mn²⁺,H₂O,Zn²⁺/Zn,V³⁺/V²⁺,and Br₂/Br^- are +0.77,+1.51,-0.76,-0.26,and +1.09 V,respectively,which is the strongest oxidizing agent?

For the cell diagram Pt|H₂(g) ,H⁺(aq) m Cu²⁺(aq) |Cu(s) Which reaction occurs at the anode?

Quiz 14: Electrochemistry

Given: PH3(g) →\rightarrow→ P4(s) ,basic solution. How many electrons appear in the balanced half-reaction?

The standard potential of the Cu2+/Cu electrode is +0.34 V and the standard potential of the cell Ag(s) |AgCl(s) |Cl-(aq) m Cu2+(aq) |Cu(s) Is +0.12 V.What is the standard potential of the AgCl/Ag,Cl- electrode?

When equilibrium is reached in an electrochemical cell,the voltage reaches its maximum value.

A cell that uses bromine to oxidize chloride ion under standard conditions at 298 K has a positive potential.True or false?

When the Ag(s) |AgCl(s) |Cl-(aq) electrode acts as a cathode,the reaction is

In the determination of iron in vitamins,Fe2+ is titrated with permanganate,MnO4-,in acidic solution.The products of the reaction are Fe3+ and Mn2+.In the balanced equation,the number of electrons transferred is

Given: N2H5+(aq) →\rightarrow→ N2(g) . How many electrons appear in the balanced half-reaction?

The standard potential of the Cu2+/Cu electrode is +0.34 V and the standard potential of the cell Pb(s) |Pb2+(aq) m Cu2+(aq) |Cu(s) Is +0.47 V.What is the standard potential of the Pb2+/Pb electrode?

If the standard potentials for the couples Cu2+/Cu,Ag+/Ag,and Fe2+/Fe are +0.34,+0.80,and -0.44 V,respectively,which is the strongest reducing agent?

What is the proper cell diagram for the reaction 2AgCl(s) + H2(g) →\rightarrow→ 2Ag(s) + 2H+(aq) + 2Cl-(aq)

Given: S2O42-(aq) →\rightarrow→ SO32-(aq) ,basic solution. How many electrons appear in the balanced half-reaction?

A cell that uses bromine to oxidize hydrogen to H+ under standard conditions at 298 K has a negative potential?

When a sample of an unknown metal is dropped into 1 M H+(aq)under standard conditions,bubbles are observed.The unknown metal could be silver.

Given: Zn(s) + OH-(aq) + H2O(l) + NO3-(aq) →\rightarrow→ Zn(OH) 42-(aq) + NH3(g) If the coefficient of NO3- in the balanced equation is 1,how many electrons are transferred in the reaction?

In a working electrochemical cell (+ cell voltage),the cations in the salt bridge move toward the cathode.

How many electrons appear in the balanced half reaction: NO3-(aq) F →\rightarrow→ NO(g) ,in acidic solution?

Given: Cr(OH) 3(s) →\rightarrow→ CrO42-(aq) ,basic solution. How many electrons appear in the balanced half-reaction?

In a working electrochemical cell (+ cell voltage),the electrons flow from the anode through the external circuit to the cathode.

If the standard potentials for the couples Fe3+/Fe2+,MnO42-0,H+/Mn2+,H2O,Zn2+/Zn,V3+/V2+,and Br2/Br- are +0.77,+1.51,-0.76,-0.26,and +1.09 V,respectively,which is the strongest oxidizing agent?

For the cell diagram Pt|H2(g) ,H+(aq) m Cu2+(aq) |Cu(s) Which reaction occurs at the anode?

Given: PH₃(g) $\rightarrow$ P₄(s) ,basic solution. How many electrons appear in the balanced half-reaction?

The standard potential of the Cu²⁺/Cu electrode is +0.34 V and the standard potential of the cell Ag(s) |AgCl(s) |Cl^-(aq) m Cu²⁺(aq) |Cu(s) Is +0.12 V.What is the standard potential of the AgCl/Ag,Cl^- electrode?

When the Ag(s) |AgCl(s) |Cl^-(aq) electrode acts as a cathode,the reaction is

In the determination of iron in vitamins,Fe²⁺ is titrated with permanganate,MnO₄^-,in acidic solution.The products of the reaction are Fe³⁺ and Mn²⁺.In the balanced equation,the number of electrons transferred is

Given: N₂H₅⁺(aq) $\rightarrow$ N₂(g) . How many electrons appear in the balanced half-reaction?

The standard potential of the Cu²⁺/Cu electrode is +0.34 V and the standard potential of the cell Pb(s) |Pb²⁺(aq) m Cu²⁺(aq) |Cu(s) Is +0.47 V.What is the standard potential of the Pb²⁺/Pb electrode?

If the standard potentials for the couples Cu²⁺/Cu,Ag⁺/Ag,and Fe²⁺/Fe are +0.34,+0.80,and -0.44 V,respectively,which is the strongest reducing agent?

What is the proper cell diagram for the reaction 2AgCl(s) + H₂(g) $\rightarrow$ 2Ag(s) + 2H⁺(aq) + 2Cl^-(aq)

Given: S₂O₄²^-(aq) $\rightarrow$ SO₃²^-(aq) ,basic solution. How many electrons appear in the balanced half-reaction?

A cell that uses bromine to oxidize hydrogen to H⁺ under standard conditions at 298 K has a negative potential?

When a sample of an unknown metal is dropped into 1 M H⁺(aq)under standard conditions,bubbles are observed.The unknown metal could be silver.

Given: Zn(s) + OH^-(aq) + H₂O(l) + NO₃^-(aq) $\rightarrow$ Zn(OH) ₄²^-(aq) + NH₃(g) If the coefficient of NO₃^- in the balanced equation is 1,how many electrons are transferred in the reaction?

How many electrons appear in the balanced half reaction: NO₃^-(aq) F $\rightarrow$ NO(g) ,in acidic solution?

Given: Cr(OH) ₃(s) $\rightarrow$ CrO₄²^-(aq) ,basic solution. How many electrons appear in the balanced half-reaction?

If the standard potentials for the couples Fe³⁺/Fe²⁺,MnO₄2^-0,H⁺/Mn²⁺,H₂O,Zn²⁺/Zn,V³⁺/V²⁺,and Br₂/Br^- are +0.77,+1.51,-0.76,-0.26,and +1.09 V,respectively,which is the strongest oxidizing agent?

For the cell diagram Pt|H₂(g) ,H⁺(aq) m Cu²⁺(aq) |Cu(s) Which reaction occurs at the anode?