How to Make Simulated Stomach Acid

Stomach acid is a strong acid that is produced and secreted by cells within the stomach. Often for science projects, you may need to make a simulated stomach acid. This can help you understand how different foods and certain drugs for stomach trouble will react with the acid in the stomach. Below is a simple guide to making your own simulated stomach acid.

Things You'll Need

• Hydrochloric acid Water Table salt Potassium chloride A glass bottle

Instructions

How to Make Simulated Stomach Acid

1. Determine how much stomach acid you'll need. It will be easiest to figure this out in metric units, such as liters. You will need this much water.

2. Obtain some hydrochloric acid. Hydrochloric acid is the main ingredient in stomach acid. You might be able to find it at a hardware store.

3. Measure out the hydrochloric acid. The concentration of hydrochloric acid in stomach acid is about 0.155 Molar (moles per liter). This means that for every liter of stomach acid you want to make, you will need 5.6 g of hydrochloric acid. Be careful, because hydrochloric acid is very strong and can burn you easily.

4. Mix the hydrochloric acid with water. The best way to do this is to add the water into your container first, and then add the acid. Make sure you put a tight cap on the bottle, and then shake it up.

5. Add other ingredients. The other main ingredients in stomach acid are potassium and sodium. For every liter of stomach acid, you will want to add 5 g of table salt and another 5 g of potassium chloride (sometimes sold to salt driveways).