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Redox and electrochemistry — Question 2

QCAA 2024, Paper 1 · 1 mark

Q2 · 2024 · Paper 1Unclassified1 mark

QUESTIONS 1–2 Questions 1–2 refer to hydrated copper sulfate and its decomposition when heated.

Hydrated copper sulfate (CuSO4·H2O) decomposes to form copper sulfate (CuSO4) and water when heated.

heat + CuSO4·H2O(s)

CuSO4(s) + H2O(g)

QUESTION 2

Determine the oxidation number of sulfur (S) in CuSO4·H2O.

(A) + 8

(B) + 6

(C) − 2

(D) − 4

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