An evil chemist's oddly blocky fortress serves as the setting for a dream quest through the elements. Well-prepared but afflicted with severe test anxiety, Mel falls asleep the night before a chemistry exam and finds herself in the Land of the Elements, helping blobby Hydrogen recover a book of spells, er, chemistry experiments snatched by the evil Elemancer. Traveling systematically through the Periodic Fortress from Alkali Metals to Noble Gases, she's forced to draw on her knowledge of molecular processes and each group's common characteristics to get past a series of elemental monsters--and, climactically, to face her fears as the sneering nemesis assaults her with pop-quiz questions: "How many elements are there?" "Is an element's atomic number the same as its weight?" "What do you call it when matter changes from a solid to a gas?" Along with rooting for the young savant, readers will have challenges of their own to face, as Chad loads the script and art with information on atoms and atomic numbers, compounds versus mixtures, ionic and covalent bonding, isotopes, allotropes, radioactivity, the periodic table's origins and organization, and how select elements of the 118 identified so far have been put to use. Mel, who like her comforting mom (the only other human figure) presents as Black, wakes up ready to tackle the ultimate test with new, and just possibly contagious, confidence in her preparation. Solid gold. (table of elements, metric conversion chart, glossary, bibliography) (Graphic nonfiction. 11-15) Copyright (c) Kirkus Reviews, used with permission.