Q50 · Practice questionComplex familiar5 marks
QUESTION 50 (5 marks)
Acidified dichromate reacts with iodide to form chromium(III) and iodine.
a) Write the balanced dichromate reduction half-equation. [2 marks]
b) Write the balanced net ionic equation. [2 marks]
c) Identify the oxidising agent. [1 marks]
WORKED SOLUTION
5 marksPractice marking scheme
; ; dichromate.
Iodide oxidation is . Multiply by three before adding. Dichromate accepts electrons and is the oxidising agent.
- Balances atoms in the dichromate half-equation. [1 marks]
- Balances charge with six electrons. [1 marks]
- Uses six iodides/three iodines. [1 marks]
- Produces the balanced net equation. [1 marks]
- Identifies dichromate as oxidising agent. [1 marks]
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