And bear in mind that sulfuric acid is only one possibility among several!
Liquid oxygen, which is also pretty easy to produce or acquire, expands quite a bit when it evaporates, and rapidly oxidizes all of your pretty organic chemistry. If you could ship enough liquid oxygen (transfigured into something else) inside a human, they would burn and explode when the transfiguration wears off.
Botulinum toxin was also mentioned in the fic and is the weapon of choice for DIY genocide.
Pyrophoric substances, transfigured and then finely ground, will start burning in an oxygen-containing atmosphere.
Obtain nuclear weapons material (the hard part) and transfigure several subcritical pieces into iron, assemble them to give one large ball, drop it (or bury it underground), and run.
Certainly not all of these are practical, but all of them sound awesome.
Also: Metallic sodium and potassium, as well as phosphorus, are quite reactive with human tissue. For bonus points you can make a mixed projectile with two transfigurations, e.g. a core transfigured from ice surrounded by a shell transfigured from sodium, which will explode once the two transfigurations end.
This is a new thread to discuss Eliezer Yudkowsky’s Harry Potter and the Methods of Rationality and anything related to it. This thread is intended for discussing chapter 97. The previous thread is at nearly 500 comments.
There is now a site dedicated to the story at hpmor.com, which is now the place to go to find the authors notes and all sorts of other goodies. AdeleneDawner has kept an archive of Author’s Notes. (This goes up to the notes for chapter 76, and is now not updating. The authors notes from chapter 77 onwards are on hpmor.com.)
The first 5 discussion threads are on the main page under the harry_potter tag. Threads 6 and on (including this one) are in the discussion section using its separate tag system.
Also: 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25.
Spoiler Warning: this thread is full of spoilers. With few exceptions, spoilers for MOR and canon are fair game to post, without warning or rot13. More specifically: