Which statements correctly describe electrolysis? During electrolysis:an electrochemical decomposition reaction occurs.electric current is supplied as the energy to perform an endergonic reaction.the electrochemical cell operates with a negative ΔG.electric current flows in a nonspontaneous direction within an electrochemical cell.

Question

Which statements correctly describe electrolysis?  During electrolysis:an electrochemical decomposition reaction occurs.electric current is supplied as the energy to perform an endergonic reaction.the electrochemical cell operates with a negative ΔG.electric current flows in a nonspontaneous direction within an electrochemical cell.

Quizplus · Accepted Answer

11ecba2d_123e_4cba_a3bf_7922785b34fe_MD0008_00 Using a loosely applied analogy, an electrolytic cell can be conceptualized as a galvanic (voltaic) cell that is operating in reverse. Although the electrolytic cells may be constructed differently (one chamber vs. two) and some chemical reactions are irreversible, accounting for these distinctions and limitations, electrolytic and galvanic cells essentially perform in an opposite manner. In a galvanic cell, a spontaneous, exergonic chemical reaction (ΔG < 0) produces electric current. Conversely, in an electrolytic cell, electric current from an external source (such as a battery) is supplied to drive a nonspontaneous, endergonic chemical reaction (ΔG > 0) within the electrochemical cell. In both galvanic and electrolytic cells, reduction takes place at the cathode and oxidation takes place at the anode, but the role of a given electrode is opposite in each cell type. The electrode functioning as the anode in a galvanic cell functions as the cathode in an electrolytic cell (and vice versa). As such, the direction of electrical current is reversed in an electrolytic cell compared with a galvanic cell. (Recall that, by convention, the direction of the electric current is taken to be opposite to the direction of electron migration.) The operation of an electrolytic cell causes electrolysis, which is the nonspontaneous, electrochemical decomposition of a compound (Number I). At the electron-deficient anode, electron-rich species (such as anions) are oxidized. For example, in the electrolysis of molten NaCl, Cl⁻ is oxidized to Cl₂ gas: 11ecba2d_123e_4cbb_a3bf_7bd86fea145c_MD0008_00 At the electron-rich cathode, electron-deficient species (such as metal cations) are reduced. In the example of the electrolysis of molten NaCl, Na⁺ is reduced to Na metal: 11ecba2d_123e_4cbc_a3bf_9571959c1459_MD0008_00 The net reaction for the electrochemical process gives the overall nonspontaneous, decomposition reaction: 11ecba2d_123e_4cbd_a3bf_7746d72f737b_MD0008_00 Because electrolysis uses an electrolytic cell, the supplied electrical current flows in a nonspontaneous direction within the electrochemical cell (Number IV), which supplies the energy needed to perform a nonspontaneous (endergonic) decomposition reaction (Number II). (Number III) Electrolysis uses an electrolytic cell that has a positive, not a negative, ΔG. Educational objective: In an electrolytic cell, electric current from an external source is supplied to provide the necessary energy to perform a nonspontaneous (endergonic), decomposition reaction of a compound within the electrochemical cell.

Which Statements Correctly Describe Electrolysis? During Electrolysis:an Electrochemical Decomposition Reaction