Which of the following reactions are always exothermic?

I. Neutralization Il. Decomposition III. Combustion

A. I and II only
B. I and III only
C. II and IIl only
D. I, II and III

Correct Answer:

Option B = I and III only

Explanation

LIST OF EXOTHERMIC REACTIONS

• any combustion reaction.
• a neutralization reaction.
• rusting of iron (rust steel wool with vinegar)
• the thermit reaction.
• the reaction between water and calcium chloride.
• the reaction between sodium sulfite and bleach (dilute sodium hypochlorite)
• the reaction between potassium permanganate and glycerol.