Question

For which among the following reactions, change in entropy is less than zero?

• A. Sublimation of iodine
• B. Dissociation of hydrogen
• C. Formation of water
• D. Thermal decomposition of calcium carbonate

Answer 1

The correct option is B Dissociation of hydrogen

In dissociation of hydrogen, change in entropy is less than zero that means negative. Dissociation of hydrogen is a non-spontaneous reaction. Hence it has entropy less than zero.

So answer is B.