Question

Are covalent bonds always formed between similar atoms???

Answer 1

Thanks for asking the question.
All the atoms wants to make them stable. Except noble gasses, they are already stable. But other atoms, they make them stable by sharing of electrons. Some atoms make bonds with different atoms to make themselves stable. While some atoms makes bond with the same kind of atoms. This type of bonding is called covalant bonding. They are formed only between similar atoms because of sharing of electrons. The main reason is that similar atoms have same elctronegativity difference, which is important for the formation of covalant bonds, and this happens only when a bond is formed between similar atoms.
Hope it helps.

Answer 2

Explanation:

Covalent bonds can be formed bw similar and dissimilar atoms also.....

ex:  methane (CH4), carbon monoxide (CO), and iodine monobromide (IBr)

As covalent bond is basically sharing of electrons bw to atoms  it can take take place with similar atoms or disimilar atoms .