Final answer:
The melting of ice and the dissolution of certain salts in water are examples of spontaneous processes with a positive or zero ΔH°.
Step-by-step explanation:
Although it is commonly believed that spontaneous processes are always exothermic, there are actually examples of processes with a positive or zero ΔH° that are still spontaneous. One example is the melting of ice at a pressure of 1 atm. Even though this process is endothermic (absorbs heat), it still occurs spontaneously at temperatures above 0°C. Another example is the dissolution of certain salts in water, such as NH4NO3, NaCl, and KBr. Although these processes also absorb heat, they still occur spontaneously.