Final answer:
Ammonia (NH3) molecules are held together in a solid state by hydrogen bonding, which is a strong intermolecular force. These forces are weaker than intramolecular forces but crucial in determining NH3's physical properties, such as its boiling point and solubility. Temperature affects these intermolecular forces, influencing the viscosity of liquids.
Step-by-step explanation:
Intermolecular Forces in NH3
Ammonia (NH3) is a molecular solid, which means it is a solid composed of neutral molecules that are held together by intermolecular forces of attraction. These forces are weaker than the intramolecular forces that hold the atoms within a molecule together. NH3 molecules exhibit a strong type of intermolecular force known as hydrogen bonding due to the presence of a very electronegative nitrogen atom bonded to hydrogen atoms. Dipole-dipole interactions and London dispersion forces are also present, but hydrogen bonding is predominant, greatly influencing the physical properties of NH3, such as its boiling point and solubility in water.
An image describing Methane bonding, even though referring to a different molecule (CH4), helps us understand the concept of intermolecular forces. The green sphere (labeled "C 1") and the white sphere (labeled "H") in methane illustrate the strong intramolecular forces within a molecule, while the dotted line between the molecules represents the weaker intermolecular forces.
Temperature has a significant effect on intermolecular forces. At higher temperatures, the kinetic energies of the molecules increase, causing the intermolecular forces to be overcome to a greater extent, which results in a decrease in liquid viscosity. Conversely, lowering the temperature reduces the molecules' kinetic energy, allowing intermolecular forces to dominate and the liquid to become more viscous.