Endothermic Dissolution Process

Steps:

• ΔH = +25 kJ/mol indicates the process absorbs heat, confirming statement 1 (endothermic).
• Heat absorption from the surroundings cools the water, confirming statement 2.
• The ammonium nitrate ions take thermal energy from water molecules during hydration, confirming statement 3.
• All statements align with the positive ΔH for the dissolution.

Why A is correct:

• Positive ΔH defines an endothermic process where the system absorbs heat from surroundings, validating all three statements per the first law of thermodynamics (ΔH = q_p).

Why the others are wrong:

• B omits statement 3, but energy transfer from water to solute occurs in endothermic dissolution.
• C omits statement 2, but heat absorption cools the solution temperature.
• D omits statement 1, but ΔH > 0 directly means endothermic.

Final answer: A