The longest word on this page is how many characters? The largest word that's possible to construct from the combination specified is blatherskites, and it consists of 13 characters.
How many actual words could one make using the combination which you've searched for? You can derive 21 words using the specified letter combination.
What's the highest scoring Scrabble word you can make? From this combination of letters, the best word to play is blackit for a total score of 15 in Scrabble.
What's an unusual word from the word combinations possible on this page? One example of a weird word from this list goes to brookite. The dictionary defines it as "A mineral consisting of titanic oxide, and hence identical with rutile and octahedrite in composition, but crystallizing in the orthorhombic system.".