How to Prepare Simulated Gastric Juice (pH 1.5–2.0) for Laboratory Experiments

Ingredients

• Hydrochloric acid (HCl)
• Sodium chloride (NaCl)
• Potassium chloride (KCl)
• Calcium chloride (CaCl₂)
• Distilled/deionized water

Procedure

1. Calculate amounts per liter: 0.1 N HCl (~3.7 mL conc. HCl), 5.9 g NaCl, 0.3 g KCl, 0.1 g CaCl₂.
2. Add HCl to water; stir.
3. Dissolve salts in small warm water separately.
4. Combine HCl solution with salt solution.
5. Bring to 1 L with water.
6. Adjust pH to 1.5–2.0 with more HCl or dilution.

Safety Notes

Wear gloves, eye protection, work in ventilated area when handling concentrated HCl.

Simulated gastric juice used for digestion, enzyme activity, and material behavior studies in acidic environments.