Two solutions (the system), each with a volume of 25.0 mL at 25.0°C, are mixed in a beaker. A reaction occurs between them, and the temperature rises to 35.0°C. After the products have equilibrated with the surroundings, the temperature is again 25.0°C and the total volume is 50.0 mL. No gases are involved in the reaction. Which relationship concerning the change from initial to final states (both at 25.0°C) is correct? Select one: A. ΔH = 0 B. q = 0 C. ΔU > 0 D. ΔU = 0 E. w = 0