Question

Which elements from periodic table possess positive electron gain enthalpy

Answer 1

this trend depends on the variation in groups and periods....
which decreases along group and increases along period s

Answer 2

➡positive electron gain enthalpy are shown by those elements which have fully filled valence shell and also half filled valence shell... because we have to provide energy to add any further electron to it... and by adding more electron it becomes unstable....

➡so... we know that all NOBLE GASSES have fully filled valence electrons.... so they have positive electron gain enthalpy...

➡HELIUM, NEON, ARGON, KRYPTON, XENON, RADON...

➡also in case of NITROGEN... we have positive electron gain enthalpy because it has half filled valence orbital... so we know that half filled and fully filled orbitals are more stable... so in this case also we have positive electron gain enthalpy

hope it helps you...
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