Final answer:
Dissolving 3.21 g of NH₄NO₃ in 100.0 g of water would likely result in approximately half the temperature change, compared to dissolving it in 50.0 g of water, which is around a drop of -2.3 °C.
Step-by-step explanation:
The question asks about the change in temperature when 3.21 g of NH₄NO₃ is dissolved in 100.0 g of water, compared to when the same amount is dissolved in 50.0 g of water, as described in Example 5.6 of a given reference material.
In that example, dissolving 3.21 g of NH₄NO₃ in 50.0 g of water resulted in a temperature decrease from 24.9 °C to 20.3 °C, a change of -4.6 °C.
Since the specific heat capacity is a property of a substance and independent of mass, if we were to double the mass of the solvent (water in this case), the temperature change would be expected to halve, assuming the system is perfectly efficient.
Therefore, dissolving the same amount of NH₄NO₃ in twice the amount of water should result in approximately half the temperature change (i.e., a drop of around -2.3 °C).