JEE Advanced levelSingle correct optionDifficulty 3 of 3pt161
Sulfur has first and second electron gain enthalpies of −200 and +640kJmol−1 respectively. For the process S(g)+2e−→SX2−(g) with 3.2 g of S atoms (S = 32), the energy change is
A84 kJ released
B44 kJ released
C440 kJ released
D44 kJ absorbed
Answer: D
Per mole: -200 + 640 = +440 kJ (net endothermic). Moles = 3.2/32 = 0.10, so energy = 0.10 x 440 = 44 kJ absorbed.