6. In which of the following reactions is a positive ion reduced? A Iodide iodine B Nickel(II) nickel(III) C Cobalt(III) cobalt(II) D Sulphate sulphite 7. In which reaction is hydrogen gas acting as an oxidising agent? A H2 + CuO H2O + Cu → B H2 + C2H4 C2H6 → C H2 + Cl2 2HCl → D H2 + 2Na 2NaH → 8. Iodide ions can be oxidised using acidified potassium permanganate solution. The equations are: How many moles of iodide ions are oxidized by one mole of permanganate ions? A 1.0 B 2.0 C 2.5 D 5.0 9. During a redox process in acid solution, iodate ions are converted into iodine. 2IO3–(aq) + 12H+(aq) + xe– I2(aq) + 6H2O(l) → To balance the equation, what is the of x? A 2 B 6 C 10 D 12 10. The following reactions take place when nitric acid is added to zinc. How many moles of NO3– (aq) are reduced by one mole of zinc? 11. One of the reactions taking place within a carbon monoxide sensor is 2CO + 2H2O 2CO2 + 4H+ + 4e− → This reaction is an example of A reduction B redox C oxidation D hydration. 12. The concentration of ethanol in a person’s breath can be determined by measuring the voltage produced in an electrochemical cell.
6. In which of the following reactions is a positive ion reduced? A Iodide iodine B Nickel(II) nickel(III) C Cobalt(III) cobalt(II) D Sulphate sulphite 7. In which reaction is hydrogen gas acting as an oxidising agent? A H2 + CuO → H2O + Cu B H2 + C2H4 → C2H6 C H2 + Cl2 → 2HCl D H2 + 2Na → 2NaH 8. Iodide ions can be oxidised using acidified potassium permanganate solution. The equations are: How many moles of iodide ions are oxidized by one mole of permanganate ions? A 1.0 B 2.0 C 2.5 D 5.0 9. During a redox process in acid solution, iodate ions are converted into iodine. 2IO3–(aq) + 12H+(aq) + xe– → I2(aq) + 6H2O(l) To balance the equation, what is the of x? A 2 B 6 C 10 D 12 10. The following reactions take place when nitric acid is added to zinc. How many moles of NO3– (aq) are reduced by one mole of zinc? 11. One of the reactions taking place within a carbon monoxide sensor is 2CO + 2H2O → 2CO2 + 4H+ + 4e− This reaction is an example of A reduction B redox C oxidation D hydration. 12. The concentration of ethanol in a person’s breath can be determined by measuring the voltage produced in an electrochemical cell.