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Railways PYQCBT 1 2016

RRB NTPC · Question 60

Which of the following chemical reactions is always endothermic in nature?

  1. Combustion reaction

  2. Decomposition

  3. Displacement reaction

  4. Combination reaction

Show answer & explanation

Answer: (B) Decomposition

Explanation

Decomposition reactions need energy to break a compound apart, so they are endothermic (e.g. heating calcium carbonate). Combustion is always exothermic.