Among all the elements which element has highest value of first ionization energy?
Hello aspirant,
The first ionization energy varies in a predictable way across the periodic table. The ionization energy decreases from top to bottom in groups, and increases from left to right across a period. Thus, helium has the largest first ionization energy , while francium has one of the lowest.



![XAT Result 2026 Expected This Week [LIVE Updates]: Date, Time, Score vs Percentile & Top Colleges](https://cache.careers360.mobi/media/presets/50X50/article_images/2026/1/13/XAT-2026-Result-Date.jpg)
