When two atoms of Florine combines, they share an electron pair to complete it's octet. This result is formation of single bond between two fluorine atoms. This process is exothermic in nature, and hence, heat is liberated during the process of bond formation. <span />
It’s c I believe because it says 209 years to complete an orbit so hint yourself ?.....
Phase 3 is the integration phrase
<span>J.j thomson a british physicist was the first to identify the electron in 1987</span>
