A possible compound would be silicon dioxide with giant covalent structure and strong covalent bonds.
It is not possible for the polar covalent compound to have a lower melting point than the non-polar covalent compound because they have ionic bonds.
Ionic compounds have higher melting points than covalent compounds. Common table salt, sodium chloride, is an ionic compound and has a melting point of 801 oC. Table sugar, sucrose, a covalent compound, has a melting point of about 186 oC.
The melting point of a compound cannot determine the bonding structure. As an example, both diamond and sodium chloride have higher melting points than 800 centigrade but are covalent and ionic compounds respectively.
Compared to ionic compounds, covalent compounds have relatively low melting and boiling points because covalent bonds are not as strong as ionic bonds, and it is the bonds which hold materials together in the solid, or more solid phases.
Ionic compounds are between metals and non-metals. Molecular (covalent) compounds are between only non-metals. (Metallic compounds are between metals and other metals) An ionic compound is a pure substance that is formed from a metal and a nonmetal. It has a fairly high melting point and is a conductor of electricity when in a molten or aqueous state. A molecular compound, on the other hand, is a pure substance that is formed from nonmetals. It has a fairly low melting point, and can only conduct electricity unless it is aqueous and polar. Another important difference between the two is that an ionic compound is a crystalline solid at standard temperature and pressure (STP), whereas a molecular compound can be in a solid, gas or liquid state at STP.
It is not possible for the polar covalent compound to have a lower melting point than the non-polar covalent compound because they have ionic bonds.
Ionic compounds have higher melting points than covalent compounds. Common table salt, sodium chloride, is an ionic compound and has a melting point of 801 oC. Table sugar, sucrose, a covalent compound, has a melting point of about 186 oC.
Zinc sulfide is a covalent compound.
Ionic compounds have melting points higher than covalent compounds.
The melting point of a compound cannot determine the bonding structure. As an example, both diamond and sodium chloride have higher melting points than 800 centigrade but are covalent and ionic compounds respectively.
Sodium chloride is an ionic compound whereas AlCl3 is a covalent compound. Ionic compounds have greater melting point due to stronger electrostatic force of attraction.
Compared to ionic compounds, covalent compounds have relatively low melting and boiling points because covalent bonds are not as strong as ionic bonds, and it is the bonds which hold materials together in the solid, or more solid phases.
Covalent compounds have a lower melting point.
Ionic compounds are between metals and non-metals. Molecular (covalent) compounds are between only non-metals. (Metallic compounds are between metals and other metals) An ionic compound is a pure substance that is formed from a metal and a nonmetal. It has a fairly high melting point and is a conductor of electricity when in a molten or aqueous state. A molecular compound, on the other hand, is a pure substance that is formed from nonmetals. It has a fairly low melting point, and can only conduct electricity unless it is aqueous and polar. Another important difference between the two is that an ionic compound is a crystalline solid at standard temperature and pressure (STP), whereas a molecular compound can be in a solid, gas or liquid state at STP.
Covalent bonds do not melt. Compounds with covalent bonds melt and the melting point depends primarily on whether there are discrete molecules held together by intermolecular forces (which have lower melting points) or giant covalent networks such as in silica or diamond (which tend to have higher melting points).
Silver iodide is an ionic compound, whereas vanillin is a covalent compound. The bonds between atoms are much stronger in ionic compounds, so the melting point is higher in AgI.
Diamond is a covalent network solid, and those types of compounds have higher melting points than other types of compound.