them to blow up a balloon? When you put vinegar and baking soda together, you get a chemical
reaction, and this chemical reaction produces carbon dioxide gas.
A chemical reaction happens when one set of substances (called the reactants) transforms into different substances (called the products). When scientists talk or write about chemical reactions, they usually write them like this:
Chemical reactions happen everywhere, all around us. When you digest your food, your body performs chemical reactions to turn your food into energy. When you sit beside a campfire and enjoy its warmth, you are being warmed by a chemical reaction. Sometimes these chemical reactions happen slowly, but sometimes they are fast and violent. One type of chemical reaction happens between acids and bases.
An acid is a substance that releases hydrogen ions (usually written as H+) when mixed in solution (that is, when it is in liquid form, like when you mix it in water). Hydrogen is just one of the building blocks that make up lots of different substances, but with acids this hydrogen ion wants to separate from
the rest of the building blocks, and go into the water. This means that when you mix an acid in water, it will push part of itself –the hydrogen—into the water, like this:
A base can be thought of as the opposite of an acid. Often, it is a substance that, if mixed in water, can take the hydrogen (H+) ions back out of solution. So, while the acid is putting H+into the solution, the base is taking them away:
look like this:
Or as a chemist would write:
NaHCO3 + CH3COOH ------------------> CO2 (gas) + H2O + CH3COONa
The vinegar (acid) and the baking soda (base) are like two towers made up of
When we mix them together, the baking soda takes one of the bricks--the H+--from the vinegar:
But now, the baking soda tower is not stable, so it falls apart! After it has fallen apart, what it turns into is water and carbon dioxide gas!
the sodium from the baking soda (the sodium is just floating around in the watery liquid, but it likes to hang out with acetate!). This carbon dioxide will escape into the air as bubbles or foam, and it is this gas you can use to blow up a balloon!
1. Measure 1 teaspoon of baking soda into a balloon.
2. Add 4 tablespoons of vinegar into a small soda bottle.
3. Carefully stretch the mouth of the balloon over the opening of the bottle.
4. Lift the balloon, and shake the baking soda into the bottle so that it mixes with the vinegar in the bottle.
5. Watch as the CO2 gas produced by the chemical reaction between the acetic acid in the vinegar and the sodium bicarbonate (baking soda) blows up the balloon!
6. When the balloon stops growing, measure how wide the balloon is with a ruler or a tape measure.
How large did the balloon get?
What happens if you double the amount of baking soda and vinegar? (That is, try adding 2
teaspoons of baking soda in the balloon and 8 tablespoons of vinegar in the bottle.) Will the balloon be twice as big? Write down what you think will happen.
Try the same experiment again, adding 2 teaspoons of baking soda to the balloon and 8 tablespoons of vinegar to the bottle.
How big does the balloon get when you double the amount of baking soda and vinegar?
Were you right about how big the balloon would get?
What happens if you change the amount of baking soda, or the amount of vinegar?
Add one teaspoon of baking soda to 8 tablespoons of vinegar. How big does the
Add two teaspoons of baking soda to 4 tablespoons of
vinegar. How big does the balloon get now?
Who can make their balloon blow up biggest? Challenge your friends to a contest, and see who can make the biggest balloon. Try different amounts of vinegar and baking soda. What combination of vinegar and baking soda produce the largest balloon?