Learning the basics of science doesn’t require hard-to-find tools and materials. This simple experiment made from potatoes invites children to understand why potatoes soaked in water and salt water can give different results.
Tools and Materials of Simple Experiment – Potatoes Soaked in Water and Salt Water
- 1 potato
- Enough water
- 2 tablespoons salt
- Knife
- Small bowl
- Spoon
Step of Simple Experiment – Potatoes Soaked in Water and Salt Water
1. Peel and clean the potatoes
2. Prepare two pieces of potato pieces, don’t need to be too big or thick. Can be made from sliced the outer edge of the potato and then this slice is split into two. Press the potato pieces to feel the density level.
3. Prepare two small bowls. Pour water into a bowl. Sprinkle two tablespoons of salt in a bowl, mix well. One other bowl let it contain plain water.
4. Put the potato pieces in both bowls one piece each. Let the potatoes soak for 30 minutes.
5. Observe what happens to the two pieces of potato
6. Potatoes soaked in salt water are softer than before soaking and don’t break easily. Potatoes soaked in plain water are firmer than the condition before soaking.
Explanation of Simple Experiment – Potatoes Soaked in Water and Salt Water
Changes in the condition of potatoes after being soaked in salt water indicate the occurrence of osmosis. Osmosis is the movement of substances contained in a hypotonic solution (low concentration) to a hypertonic solution (high concentration) through a semipermeable membrane. The softening of potatoes soaked in brine is caused by the process of osmosis, namely the release of water contained in the potatoes into a brine solution. This process, also called plasmolysis, occurs due to a difference in pressure or concentration of the liquid. The concentration of the substance in the potato is lower than the pressure in the salt solution in the bowl. This condition causes the semipermeable membrane of the potato to be penetrated by the salt solution so that the water content in the potato decreases.
Plain water soaked potatoes remain firm and even tougher than before soaking. This is due to the hypotonic nature of water. Water from the outside is absorbed by the cells inside the potato causing it to swell and harden than before. A simple experiment with easy-to-find ingredients is hoped to help explain the theory of osmosis in potatoes soaked in water and salt water
