質問: is 何か ;なにか or なんか is 何か ;なにか or なんか
回答: that depends on the context, or whether the sentences are formal or casual. when they are formal, it's definitely なにか. when you chat with your friends, it sometimes might be なんか, but in many cases, the receiver can't see which the sender changed into 何か, なにか or なんか. i think exactly なんか is supposed not to be changed into kanji. so i haven't seen any books (including novels and papers) have 何か which is read as なんか. in short, 何か is basically read as just なにか.