Here's why:

* Hydrogen's Electronic Configuration: Hydrogen has only one proton and one electron. Its electron configuration is 1s¹.

* Stability: Atoms are most stable when their outermost electron shell (also called the valence shell) is full. For hydrogen, its first shell can hold a maximum of two electrons.

* Octet Rule: While the octet rule (atoms want eight electrons in their outer shell) applies to most elements, hydrogen is an exception. It only needs two electrons to achieve stability.

Therefore, hydrogen will readily form a chemical bond (like a covalent bond) to share an electron with another atom, giving it the desired two electrons in its valence shell.