The interparticle forces are the strongest in: Ammonia Ethyl alcohol Carbon dioxide Sodium bromide

To determine which substance has the strongest interparticle forces, we need to compare the types of intermolecular forces present in each substance.

1. Ammonia (NH3): Ammonia molecules are held together by hydrogen bonding, which is a strong intermolecular force. Hydrogen bonding occurs when a hydrogen atom is bonded to a highly electronegative atom (in this case, nitrogen) and is attracted to another electronegative atom (such as nitrogen or oxygen) in a neighboring molecule.

2. Ethyl alcohol (C2H5OH): Ethyl alcohol also exhibits hydrogen bonding due to the presence of the hydroxyl group (-OH). This makes it a strong intermolecular force.

3. Carbon dioxide (CO2): Carbon dioxide molecules are held together by weak London dispersion forces, which are the result of temporary fluctuations in electron distribution. These forces are relatively weaker compared to hydrogen bonding.

4. Sodium bromide (NaBr): Sodium bromide is an ionic compound, meaning it consists of positively charged sodium ions (Na+) and negatively charged bromide ions (Br-). The interparticle forces in ionic compounds are strong electrostatic attractions between oppositely charged ions.

Based on the types of intermolecular forces present, we can conclude that ammonia and ethyl alcohol have the strongest interparticle forces due to hydrogen bonding. Carbon dioxide has weaker forces due to London dispersion forces, and sodium bromide has strong interparticle forces due to ionic bonding.