An acid is a substance that reacts with a base. They are usually identified as a sour tasting chemical. Common acids found in the kitchen are lemons, apple juice, orange juice, vinegar and black coffee. A base is a substance that will neutralize an acid. Common bases found in a kitchen are baking soda and egg whites.
In the 3 Science experiments below kids with work with Acids and Bases.
Question: How Can You Tell an Acid from a Base?
Materials: can of red cabbage, strainer/colander, bowl, 3 glass jars, 1 tablespoon of vinegar, 1 tablespoon of baking soda, 1 tablespoon of distilled water, can opener
Step 1: Open the can of red cabbage, using the strainer/colander drain the cabbage juice over the bowl.
Step 2: Put 2 tablespoons of red cabbage juice into each of the three glass jars.
Step 3: Add 1 tablespoon of vinegar to the first jar, add 1 tablespoon of baking soda to the second jar and add 1 tablespoon of distilled water to the third jar.
Step 4: Watch what happens and record your results. What color did the liquids in the jar turn?
What Happened in the Jars?
The red cabbage juice is a chemical indicator. A chemical indicator is a substance that turns color when other substances are present. In the first jar you added vinegar which is an acid to the red cabbage juice. The red cabbage juice turned redder. The stronger the acid the stronger color the chemical indicator (red cabbage juice) will turn. The baking soda (base) was added to the second jar. You will notice that the chemical indicator (red cabbage juice) turned green. In the third jar you added distilled water. The distilled water is a neutral property. You will notice the the chemical indicator (red cabbage juice) did not change colors.
Question: What Happens When you Mix an Acid with a Base?
Materials: 1 cup water, 1/2 cup vinegar, 1 cup orange juice, 3 teaspoons baking soda, 3 cereal bowls
The orange juice and vinegar are your acids and the baking soda is the base.
Step 1: Pour the water in the first bowl, vinegar in the second bowl and orange juice in the third bowl
Step 2: Pour 1 teaspoon of baking soda into each of the bowls.
Step 3: Watch what happens and record your results.
What Happened in the Bowls?
The bowls with the vinegar and orange juice started to fizz and became bubbly. When the baking soda (a base) combined with the vinegar and the orange juice (the acids) a chemical reaction occurred and a new substance was created carbon dioxide. The fizzing and bubbles tat you see are the carbon dioxide begin released. In the bowl with only water now bubbling or fizzing occurred, why? This is because water is neither a base or and acid. It is a neutral property.
Question: What Happens When You Cook a Vegetable in and Acid or a Base?
Materials: 3 cups of water, 3 small saucepans, 1 1/2 cups frozen broccoli florets, 1 tablespoon lemon juice, 1 teaspoon baking soda.
As with any project that requires a stove, adult supervision is required
The lemon juice with be the acid and the baking soda will be the base in this experiment.
Step 1: Pour 1 cup of water in each of the saucepans.
Step 2: Pour 1/2 cup of the frozen broccoli florets in each of the saucepans.
Step 3: Pour 1 tablespoon of lemon juice in the first saucepan, Pour 1 teaspoon of baking soda in the second saucepan, pour nothing in the third saucepan.
Step 4: Let the broccoli cook for 7 minutes.
Step 5: Watch what happens and record your results.
What Happened to the Broccoli?
The broccoli cooked in the baking soda (the base) will be the mushiest and a bright green color. The broccoli cooked in the lemon juice (the acid) will be a yucky olive green color. The broccoli cooked in the water will stay it’s natural green color.
Why Did the Color Change?
Green vegetables are rich in chlorophyll. Chlorophyll is what gives vegetables and grass their green color. When an acid (the lemon juice) was added to the water to cook the broccoli a chemical reaction occurred between the acid and the chlorophyll, that chemical reaction caused the broccoli to turn that yucky olive green color. When baking soda (the base) was added to the water to cook the broccoli the broccoli became mushy, why? The baking soda destroyed the cell walls of the plant (broccoli) causing to to become very mushy. Nothing happened to the broccoli cooked in the saucepan with just water because water is neither an acid or a base. It is a neutral property.
Question: How do you Turn Milk into Glue
We can drink milk, pour it into our cereal and use it for many recipes, but have you ever thought you can use it as glue? Now you can turn milk into glue with these two fun science experiments. Try them both to find out which one makes a better glue. Follow the step-by-step directions below to make your very own milk glue
1 1/2 cup milk
3 teaspoons of white vinegar
Step 1: Pour your 1 1/2 cups of milk into the pan over medium heat. Let the milk heat up until it is warm (never leave children unattended while using the stove).
Step 2: Once the milk is warm add the 3 teaspoons of white vinegar.
Step 3: Over low to medium heat stir the mixture. You will see milk lumps or curds start to appear. This happens when the liquid and solids start to separate.
Step 4: Once you have a lot of lumps strain the liquid using a strainer.
Step 5: You should be able to mold the lumps into a ball. It will be slimy.
Step 6: Put the lump back into the pan. Add a tablespoon of baking soda and a small amount of water.
Step 7: Stir and heat the mixture on medium heat until it starts to bubble.
Step 8: Once the mixture bubbles remove it from the heat and let it cool.
Step 9: It should look like a thick paste, it not continue to add baking soda and water until it is a paste consistency.
Step 10: Try using it as glue.
How did this happen? When you added the vinegar to the milk it caused a chemical reaction. The milk separated into two parts the liquid and the solid (the milk lumps or curds) The curds or lumps are the milk protein called casein. Casein is a long molecule that bends like plastic forming a natural glue. When you added the baking soda (a base) to the vinegar (acid) another chemical reaction took place. The bubbles that you saw when the mixture was heating was the carbon dioxide giving off as part of the chemical reaction turning the milk lumps or curds into a sticky, paste glue.
No heat way to try this experiment
1/2 cup milk
2 teaspoons white vinegar
1/4 teaspoon baking soda
2 tall cups
Step 1: Pour 1/2 cup of milk into one cup.
Step 2: Add 2 teaspoons of white vinegar to the milk and stir.
Step 3: Put the coffee filter loosely over the second cup and secure it with a rubber band. The coffee filter should be drooping a little in the center.
Step 4: Slowly pour the milk and white vinegar mixture over the coffee filter.
Step 5: Let the liquid drip through the coffee filter. This takes a while I actually let the mixture drip for about an hour so It was all out.
Step 6: Once all the liquid is gone scrape off the milk lumps.
Step 7: Place the milk lumps (curds) into a bowl then add 1/4 teaspoon of baking soda. Mix well
Step 8: The mixture should become sticky and paste like. Try using it as glue.
Other Milk Glue Experiment Ideas:
Where you able to get glue from these experiments? Which experiment worked? Try changing the amount of milk or baking soda what happens? Try using whole, 2% and 1% milk which one made the best glue?