Education:Science Projects: Dissolving Rock
What
you need
• 3 small drinking glasses
• lemon juice
• vinegar
• water
• 3 pieces of white chalk
What you do
1. Fill the glasses part way, one with lemon juice, one with vinegar, and one with water.
2. Put one piece of chalk in each of the glasses, submerging part of it in the liquid.
3. Place the glasses in a safe place where they won't be knocked over.
4. Check on the glasses now and then over the next three to four days and note what you see happening. Why do you think you're getting this result?
The
effects of acid rain
When you breathe out, you release the gas carbon dioxide (C02) into the air. It's one of the gases found in the Earth's atmosphere. When carbon dioxide dissolves into raindrops, it causes the rain to become naturally acidic, and this natural acid rain slowly dissolves and erodes rocks over time. But carbon dioxide is also given off in large quantities by our cars and factories, so we're releasing more and more of it into the atmosphere. That makes more acid rain, and makes erosion happen more quickly on the Earth's surface.
The chalk you used in the experiment is made of the rock limestone. When acids react with limestone, they eat away at the rock and start to break it apart. Lemon juice and vinegar are acids, and you saw how they affected the chalk. They are much stronger than acid rain, so the erosion happens more quickly. But you can see how acid rain would affect rocks, and even mountains, over hundreds and thousands of years.
