Final answer:
The provided excerpts do not contain any information about Sergei hitting Yonatan with a stove burner, and thus an accurate answer cannot be given without further context.
Step-by-step explanation:
The quoted passages do not provide any context about someone named Sergei hitting a person named Yonatan with a stove burner. It appears there has been some misunderstanding or mixing of two separate accounts. The first passage describes a kitchen fire accident with a character named Bibi, and the second passage involves historical figures during the Great Patriotic War, with no direct connection to the alleged incident involving Sergei and Yonatan. Without additional context or information regarding Sergei and Yonatan, it's not possible to provide a factual answer to why Sergei hit Yonatan, as there are no details pertaining to such an event within the provided text excerpts.