A 20.0 mL sample of gastric juice was taken from a patient suspected of having hypochloridia (low stomach acid). The sample was taken several hours after a meal so there was no ingested food or drink, and it was assumed no buffers were present. The sample required 5.5 mL of 0.0019 M NaOH to titrate the sample to neutrality. What was the pH of the gastric juice?