The correctdecreasingorder of firstionizationenthalpiesof fiveelements

1.	The correctdecreasingorder of firstionizationenthalpiesof fiveelementsof thesecondperiodis
Answer» `Be gtB gt C gt N gt F ` `N gt F gt C gt B gt Be ` `F gt N gt C gt Be gt B` `N gt F gt B gt C gt Be` Solution :Aswe MOVE fromleftto rightacrossa PERIOD`Delta_(i) H_(1)` generallyincreases.ThusF has THEHIGHEST`Delta_(i)H_(1)` .But asdiscussedin Ans. 55 above in spiteof highernuclear charge of B,`Delta_(i) H_(1)` of Beis higherthan thatof B. Combiningthesetwo TRENDS, the`Delta_(i)H_(1)` of thefiveelementsdecreasesin theorder : `F gt N gt C gt Be gt B` i.e.,option( c) is correct.

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