Final answer:
Milk stored in the refrigerator will eventually spoil due to the energy of its molecules, which will react over time and make the milk sour.
Step-by-step explanation:
When milk is stored in the refrigerator, the molecules in the milk have less energy, which means that fewer molecules will react and cause the milk to spoil. However, over time, even in the refrigerator, the milk will spoil because the higher energy molecules will eventually have enough energy to react, resulting in the milk becoming sour. This is due to the temperature effect on reaction rate, which is utilized by society in food storage to slow down the processes that cause food to spoil.