Strong and weak nuclear forces... 2 of the 4 fundamental forces of the universe. That's like asking why does the earth orbit the sun.
What structure that results when atoms are join together by covalent bond is called?
Compound if different atoms.
By sharing electrons.
molecules / compounds
Atoms 'join' together by forming chemical bonds in order to obtain better stability than the existence of individual atoms.
When different kinds of atoms join together, they form molecules or compounds. The specific arrangement and types of atoms will determine the properties and characteristics of the resulting substance.
molecule
atoms
Atoms
A compound.
a compound
Two atoms of hydrogen and one atom of oxygen.