For a spontaneous process in an isolated system, the change in entropy is positive. Hence, (A) is correct.
JEE Main 2007 — Chemistry Physical Chemistry
Identify the correct statement regarding a spontaneous process
Held on 30 Apr 2007 · Verified 6 Jul 2026.
For a spontaneous process in an isolated system, the change in entropy is positive
Endothermic processes are never spontaneous
Exothermic processes are always spontaneous
Lowering of energy in the reaction process is the only criterion for spontaneity
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80 mL of a hydrocarbon on mixing with 264 mL of oxygen in a closed U-tube undergoes complete combustion. The residual gases after cooling to 273 K occupy 224 mL. When the system is treated with KOH solution, the volume decreases to 64 mL. The formula of the hydrocarbon is :
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