Which characteristic best explains the difference in melting behavior of covalent substances and ionic substances? lonic substances have weaker intermolecular attractions. lonic substances usually have stronger atomic bonds. Covalent substances have weaker intermolecular attractions Covalent substances usually have stronger atomic bonds

The question is asking about the difference in melting behavior between covalent substances and ionic substances. The melting behavior of a substance is determined by the strength of the forces holding its particles together. In covalent substances, the atoms are bonded together by covalent bonds, which are strong bonds that involve the sharing of electron pairs between atoms. This results in a strong attraction between the atoms, which requires a lot of energy to overcome, leading to a high melting point. On the other hand, ionic substances are held together by ionic bonds, which are weaker than covalent bonds. These bonds involve the attraction between oppositely charged ions, which is weaker than the sharing of electrons in covalent bonds. Therefore, less energy is required to overcome these bonds, leading to a lower melting point. So, the characteristic that best explains the difference in melting behavior of covalent substances and ionic substances is that covalent substances usually have stronger atomic bonds.