Final answer:
The four types of chemical bonds are non-polar covalent, polar covalent, hydrogen, and ionic. Metallic bonds are another type of bonding found in metals.
Step-by-step explanation:
The four types of chemical bonds by which substances are held together are non-polar covalent, polar covalent, hydrogen bonds, and ionic bonding.
- Non-polar covalent bonds occur when two atoms share a pair of electrons equally because they have similar electronegativity.
- Polar covalent bonds are formed when two atoms share a pair of electrons unequally, leading to partial charges on the atoms due to differing electronegativity.
- Hydrogen bonds are not true chemical bonds but strong dipole-dipole forces that occur when a hydrogen atom covalently bonded to a highly electronegative atom is attracted to another electronegative atom.
- Ionic bonds form when electrons are transferred from one atom to another, resulting in a positive ion (cation) and a negative ion (anion) that attract each other.