Homemade Volcano

What we wonder?

Can we make a homemade volcano?

 What we need?

Small plastic bottle

Play dough 

Baking soda

Vinegar

Liquid dish soap

Orange food coloring

Warm water

What we need to do?

1. Cover plastic bottle with play dough leaving opening uncovered. 

2. Put small plastic animals and trees near the volcano. 

3. Add a few drops of orange food coloring into the volcano. 

4. Pour warm water into the volcano using a funnel. 

5. Add few drops of dish soap to give nice flow of lava. 

6. Add 2 tablespoonfuls of baking soda into the volcano. 

7. This is extra fun part-exaggerate that the volcano will erupt and the lava would burn our bodies.  Iesha got away as far as she can since she still wants to enjoy life. 

8. Slowly pour in the vinegar.  Obviously, this is the fun part! 

Result:

Yes, we can make a homemade volcano using baking soda and vinegar.

What actually happened?

What actually happens is this: the acetic acid (that's what makes vinegar sour) reacts with sodium bicarbonate (a compound that's in baking soda) to form carbonic acid: CH3COOH + NaHCO3 ---> CH3COONa + H2O + CO2. It is really a double replacement reaction. Carbonic acid is unstable, and it immediately falls apart into carbon dioxide and water (it's a decomposition reaction). The bubbles you see from the reaction come from the carbon dioxide escaping the solution that is left. Carbon dioxide is heavier than air, so, it flows almost like water when it overflows the container. It is a gas that you exhale (though in small amounts), because it is a product of the reactions that keep your body going. What's left is a dilute solution of sodium acetate in water. (Source: here)

How I explained to them?

Dalam cuka ni ada acetic acid, sebab tu bau dia masam.  Cuba Iris bau, cuba Iesha bau. Masam tak? Dalam baking soda ni pulak ada sodium bicarbonate.  Bila kita campur cuka dan baking soda, dia akan keluar bubble yang banyak macam Iris dan Iesha tengok tadi tu. Nama dia carbon dioxide.  OK?

They responded nothing on acetic acid bla bla. They just repeated the experiments again and again.  They just loved to kill the plastic animals and trees.  Obviously they had great time with science.