Covalent bonds usually form between two or more nonmetals such as H2, HF, H2O, NH3 or CH4.
carbon, nitrogen, hydrogen and other nonmetals and metalloids.
a non-metal with a non-metal. eg hydrogen and oxygen
Mostly metals and metalloids.
hydrogen
Covalent or molecular compounds form when elements share electrons in a covalent bond to create molecules.
Rule of thumb answer is covalent bonds form between non metal elements.
Aluminium will form covalent bonds with other elements if the difference in the electronegativities between the two elements are below 1.7
Covalent bonds usually form between two nonmetals/
This element is carbon.
Covalent or molecular compounds form when elements share electrons in a covalent bond to create molecules.
Rule of thumb answer is covalent bonds form between non metal elements.
Aluminium will form covalent bonds with other elements if the difference in the electronegativities between the two elements are below 1.7
Barium does not form covalent compounds with other elements.
Covalent bonds usually form between two nonmetals/
This element is carbon.
Elements with intermediate electronegativities, such as carbon and hydrogen.
Why does group 4A elements tend to form covalent bonds rather than ionic bonds? 
Nitrogen, carbon, and phosphorus can all form triple covalent bonds.
covalent bonds
Covalent bonds are between nonmetals.
Nonmetals form covalent bonds.