An iridium-rich layer of clay, glass spherules, and shocked quartz grains strongly suggest that the K-T boundary extinctions were at least in part caused by .

Ok where is the image ?

☆ionisation energy increases across a period from na -> ar☆ionisation energy decreases down a group from li -> fr☆ionic radius decreases across a period from na -> cl☆ionic radius increases down a groupfrom f -> ii hope it clarifies your doubts

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