Final answer:
The pH of the gastric juice after titration with 7.2 mL of 0.1 M NaOH to reach neutrality is 7, indicating that the resulting solution is neutral.
Step-by-step explanation:
To calculate the pH of a solution after adding sodium hydroxide (NaOH) to gastric juice, we need to first understand the neutralization reaction that occurs during titration. The student's question suggests that 10 mL of gastric juice is titrated with 7.2 mL of 0.1 M NaOH to reach neutrality. Gastric juice is primarily composed of hydrochloric acid (HCl), which is a strong acid, and its reaction with NaOH, a strong base, results in the formation of sodium chloride (NaCl) and water.
Since the pH scale is logarithmic and a pH of 7 is considered neutral, a titration that results in neutrality would imply a pH of 7. Thus, when 7.2 mL of 0.1 M NaOH is used to titrate the gastric juice, the resulting solution will have a pH of 7, indicating that it is neutral. It is important to note that this is a simplified calculation that assumes complete neutralization and does not take into account the buffer capacity or specific composition of the gastric juice.