Atoms can (and do) bond constantly; it's how they form molecules. Sometimes, in an atomic tug-of-war, one atom pulls electrons from another, forming an ionic bond. Atoms can also play nicely and share electrons in a covalent bond. From simple oxygen to complex human chromosome 13, George Zaidan and Charles Morton break down the humble chemical bond.
Join award winning teachers Jonathan Bergmann & Aaron Sams as they interactively teach Chemistry:
Bonding-4: Covalent Bonds
Source: Flipped Learning