Answer:
Covalent
NO₂, CCl₄, CH₄, HF, H₂O, N₂
Ionic
MgCl₂, NaCl, LiBr, FeCl₃, AlO₃, Mg₃P,
Step-by-step explanation:
Ionic bonds occurs between a metal and non-metal, while covalent bonds occurs between two non-metals.
Nitrogen and oxygen are non-metals, hence the bonds between nitrogen dioxide are covalent bonds. Thus, NO₂ is a covalent compound.
Same concept applies to carbon tetrachloride (CCl₄), methane (CH₄), hydrogen fluoride (HF), water (H₂O) and nitrogen (N₂).
The remaining compounds are ionic compunds. Let's take magnesium chloride (MgCl₂) as an example. Magnesium is a metal, while chlorine is a non-metal. Thus, the bonds formed between these atoms are ionic bonds.
Look at the position of the elements in the periodic table to identify which are metals or non-metals.