Final answer:
Covalent, ionic, and metallic compounds can exist as liquids, solids, or gases.
Step-by-step explanation:
There are three types of compounds that can exist as liquids, solids, or gases: covalent, ionic, and metallic compounds.
Covalent compounds are formed when atoms share electrons. These compounds usually have low melting and boiling points, which allow them to exist as gases or liquids at room temperature, such as water (H2O) and methane (CH4).
Ionic compounds are formed through the transfer of electrons between atoms. They often have high melting and boiling points, leading to their existence as solids at room temperature, such as sodium chloride (NaCl) and potassium nitrate (KNO3).
Metallic compounds have a lattice structure consisting of positively charged metal cations surrounded by a sea of delocalized electrons. Some examples include iron (Fe), copper (Cu), and aluminum (Al). These compounds can exist as solids at room temperature.
Learn more about Types of compounds that can exist in different states