Which statement best describes viscosity in syrups and elixirs?

• A. Syrups are more viscous than elixirs
• B. Elixirs are more viscous than syrups
• C. They have similar viscosity
• D. Viscosity depends on flavoring

Answer: (A)

Viscosity is the resistance of a liquid to flow. In syrups, the liquid is a highly concentrated sugar solution; the extensive hydrogen-bonding and strong solute–solvent interactions from the sugars create a thick, sticky liquid that moves slowly. Elixirs, on the other hand, are hydroalcoholic solutions. The alcohol acts as a cosolvent that reduces those strong interactions and lowers the overall resistance to flow, so elixirs are typically less viscous and flow more easily than syrups. Temperature also plays a role (heating lowers viscosity), but the fundamental difference is the high sugar concentration in syrups versus the alcohol-containing solvent in elixirs. So syrups are more viscous than elixirs.