Alkaline metal-group 1
Alkaline earth metals-group 2
halogens=group 7
noble gases-group 8 or o
transition metals are the actinides and the lactanides below the periodic table
Explanation:
The electronegativity difference in C-C and C-H atoms is quite low. This means smaller the electron cloud. This further means larger bond length that is electron's are further from the nucleus. hence, higher potential energy of C-C and C-H bonds.
On the contrary, C-O and H-O have large difference in electronegativity( O is high electronegative element) . This means smaller bond length. Electron's near the nucleus. Thus, lower potential energy of bonds.
It is an exothermic reaction
Calcium fluoride: CaF₂
Ca(2+) >>> Ar (argon)
F(-) >>> Ne (neon)