Each atom of Group I element has one electron in its outermost shell. On reaction, the atom loses one electron to become an ion with 1+ charge in order to attain an octet or a doublet (for helium only). For example, Na atom loses one electron to attain the octet electronic configuration 2, 8.
Too lazy to use the Internet?
Surprising how many people get their education on Yahoo! Answers. Could be why the world is so screwed up nowadays.If you can't cook, get out of the kitchen.