Answer :
Final answer:
The final pH of chyme after mixing with pancreatic juice in the duodenum achieves a slightly alkaline level of 7.1 to 8.2, primarily due to bicarbonate ions from pancreatic juice neutralizing the acidic chyme from the stomach.
Explanation:
The final pH of partially digested food, known as chyme, after it has been mixed with pancreatic juice in the duodenum is typically slightly alkaline, ranging from 7.1 to 8.2. This change in pH occurs because pancreatic juice contains sodium bicarbonate, which neutralizes the highly acidic chyme that moves from the stomach into the small intestine. Additionally, the bicarbonate ions create an optimal environment for the activity of digestive enzymes that continue the process of breaking down nutrients such as sugars, proteins, and fats.