Final answer:
Ionic compounds involve the transfer of electrons and have high melting and boiling points, while molecular compounds involve the sharing of electrons and have weaker intermolecular forces.
Step-by-step explanation:
The observed differences in the properties of ionic and molecular compounds can be attributed to the types of bonds they form and the strength of these bonds. Ionic compounds involve the transfer of electrons from one atom to another, resulting in the formation of positive and negative ions that are held together by electrostatic attraction. This gives ionic compounds high melting and boiling points, as well as the ability to conduct electricity when dissolved or molten.
On the other hand, molecular compounds involve the sharing of electrons between atoms. The shared electrons form covalent bonds, which can be either polar or nonpolar, depending on the electronegativity difference between the atoms involved. These compounds generally have lower melting and boiling points compared to ionic compounds because the intermolecular forces between molecules are weaker.
For example, sodium chloride (NaCl) is an ionic compound that forms a lattice structure due to the strong electrostatic attractions between the positively charged sodium ions and negatively charged chloride ions. In contrast, methane (CH4) is a molecular compound where four hydrogen atoms each share a pair of electrons with a carbon atom, leading to the formation of a tetrahedral shape.
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