Question

under which conditions will sugar most likely dissolve fastest in a cup of water?
○ a sugar cube with stirring at 5°c
○ a sugar cube without stirring at 15°c
○ sugar crystals with stirring at 15°c
○ sugar crystals without stirring at 5°c

Explanation:

To determine the fastest dissolution of sugar in water, we consider factors affecting the rate of dissolution: temperature, stirring, and surface area. Higher temperature (15°C is higher than 5°C) increases the kinetic energy of molecules, speeding up dissolution. Stirring increases the contact between sugar and water. Sugar crystals have a larger surface area than a sugar cube (as crystals are more broken down, exposing more surface to water). Comparing the options:

• Option A: Low temperature (5°C) and sugar cube (less surface area) with stirring.
• Option B: No stirring and sugar cube (less surface area) at 15°C.
• Option C: Sugar crystals (more surface area), stirring, and 15°C (higher temp) – all factors that maximize dissolution rate.
• Option D: No stirring, sugar crystals, and 5°C (low temp) – least favorable.

Thus, option C has the combination of higher temperature, stirring, and larger surface area (from sugar crystals) to dissolve sugar fastest.

Answer:

C. sugar crystals with stirring at 15°C