QCEVault

Redox and electrochemistry — Question 137

Original QCE Vault practice · 6 marks

Q137 · Practice questionComplex familiar6 marks

QUESTION 137 (6 marks)

Two electrolytic cells are connected in series and therefore receive the same charge. Cell A deposits Ag from Ag⁺; cell B deposits Cu from Cu²⁺. A current of 0.500 A flows for 900 s. Cell A has 100% deposition efficiency. Cell B deposits 0.126 g Cu. Use F = 96485 C mol⁻¹, M(Ag) = 107.9 g mol⁻¹ and M(Cu) = 63.55 g mol⁻¹.

(a) Calculate the silver mass deposited. [3 marks]

(b) Calculate the copper mass expected at 100% deposition efficiency. [2 marks]

(c) Calculate the copper deposition efficiency. [1 marks]

Question linkSyllabus coverage

Related questions

  1. Q1 · 2025 QCAA · Paper 1 · 1 mark
    QUESTION 1 Which species is produced at the cathode during the electrolysis of an aqueous copper sulfate (CuSO4) solution using platinum electrodes? (A) Cu(s) (B) H2(g) (C) O2(g) (D) SO2(aq)
    Redox and electrochemistry
  2. Q6 · 2025 QCAA · Paper 1 · 1 mark
    QUESTION 6 Determine which statement is true for an electrolytic cell used for electroplating. (A) The redox reaction is spontaneous. (B) The anode is the object to be plated. (C) The cathode is reduced to replenish the metal ions. (D) The electrolyte contains the metal ions that plate the object.
    Redox and electrochemistry
  3. Q10 · 2025 QCAA · Paper 1 · 1 mark
    QUESTION 10 Methane (CH4) reacts with water to produce carbon monoxide (CO) and hydrogen (H2). CH4(g) + H2O(g) → CO(g) + 3H2(g) Determine the reducing agent. (A) H in H2 (B) C in CH4 (C) H in CH4 (D) O in H2O
    Redox and electrochemistry
  4. Q15 · 2025 QCAA · Paper 1 · 1 mark
    QUESTIONS 15–16 Questions 15–16 refer to the galvanic cell shown. Zn(s) | Zn2+(aq) || Ag+(aq) | Ag(s) V Salt bridge Zn Ag QUESTION 15 Calculate the cell potential for the galvanic cell under standard conditions. (A) +0.04 V (B) +0.84 V (C) +1.56 V (D) +2.36 V
    Redox and electrochemistry