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O-LevelChemistryAcids, Bases & Salts5070/12 · May/June 2016 · Q301 Mark

Hydrated sodium carbonate decomposes when heated in a Bunsen burner flame. Which equation shows this decomposition correctly?

A2Na2CO3.10H2O(s) → 4Na(s) + 2CO2(g) + O2(g) + 10H2O(g)
BNa2CO3.10H2O(s) → Na2CO3(s) + 10H2O(g)
CNa2CO3.10H2O(s) → NaHCO3(s) + NaOH(s) + 9H2O(g)
DNa2CO3.10H2O(s) → Na2O(s) + CO2(g) + 10H2O(g)

✓ Correct answer

B: Na2CO3.10H2O(s) → Na2CO3(s) + 10H2O(g)

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About this question

Topic
Acids, Bases & Salts, O-Level Chemistry (syllabus 5070). Multiple choice, 1 mark.
Source
O-Level Chemistry, May/June 2016 Paper 1 Variant 2, question 30.

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