How will a chocolate chip cookie react to different levels of baking soda and baking powder.

I will bake multiple batches of chocolate chip cookies. Every time, I will add a different amount of baking soda and/or baking powder.
Alanna V
Grade 6


I think that the more baking powder and soda in the cookie, the more the cookie will rise and grow. If you use baking powder instead of baking soda, I think the cookie will rise more and then collapse.


Baking soda is also known as sodium bicarbonate. It is used in many ways including baking, cleaning, insect bite relief, natural mouthwash and many more. Baking soda is made by mixing carbon, sodium, hydrogen and oxygen together. This white crystal powder  is a type of salt and is most commonly used as a leavening agent. Baking soda is  a fast-acting chemical, used to make many foods. When baking soda is mixed with an acid, it will react and make CO2 bubbles. Those bubbles make the cookies lighter and fluffier.  Baking Powder and Baking soda commonly get mixed up. Baking powder is made of baking soda and another dry acid such as cream of tartar. Both powders are used as leavening agents but they are very different. When baking powder is mixed with acid it also bubbles and releases CO2. Baking powder is sometimes a double-acting leavening agent which means even though it has already been activated, it can be activated again. When food containing baking powder is in contact with heat (such as put in an oven) it will activate again. Not adding enough powder will make the treat not rise and be less chewy. You need to put a leavening agent in a cookie to make sure it will rise and be tender and chewy. If you change the amount of other ingredients it will also cause the cookie to not rise and taste funny. Baking soda helps the cookie spread so as a result the more baking soda the bigger the cookie. When the treat rises it makes the cookie light and fluffy which will end with a better cookie. Knowing this you need to add enough powder to make the cookie rise, but adding too much can make the cookie taste soapy or bitter. It can also make the cookie rise and then collapse. It will collapse because the bubbles will grow and pop and then the cookie will collapse. Sometimes a cookie will not collapse but will rise an extreme amount.


Controlled Variable

There are many controlled variables in my experiment. One controlled variable is all the other ingredients, like the flour. The amount of each ingredient stays the same through all the experiments. Another controlled variable is the temperature of the oven (350 degrees). To keep these variables controlled, I will use a knife to make sure the measurement is exact. This method will make sure the amount does not change.

Manipulated Variable

To change the manipulated variable I will change the amount of baking soda and baking powder. To change the amount of baking soda and powder I will use different measuring cups. (teaspoon) 

Responding Variable

To measure the responding variable, measure how much the cookie has risen. (mm)



  1. Preheat the oven to 375F degrees.
  2. In a medium bowl, whisk together the flour, baking soda and salt.
  3. In a large bowl, cream together the butter, granulated sugar, brown sugar and vanilla extract until light and fluffy. 
  4. Add in the eggs one at a time mixing well in between each addition.
  5. On low speed, slowly add the dry ingredients into the wet ingredients.
  6. Fold in the chocolate chips.
  7. Place 2 tablespoonfuls of dough onto the baking sheet 2 inches apart.
  8. Bake in the oven for 7-9 minutes.
  9. Let it sit on the tray for 1 minute to cool.  
  10. Transfer to a wire rack to cool completely.
  11. After the cookies have cooled, Measure how tall/wide the cookies are.




Amount of baking soda and baking powder

Width of cookie (cm)

Height of cookie (cm)

Other observations (color)

Normal ( 2 teaspoons of baking soda) 

7.3, 7.5, 7.6, 7.7, 7.7, 7.8

1.8, 1.9, 2.2, 2.3, 2.2, 2.4

Dark brown, Chocolate chips melted, Not stuck to the pan, soft, chewy, very pale, cracks.

No baking soda or baking powder 

4.6, 4.4, 4.2, 4.7, 4.3, 4.4

2.3, 2.4, 2.4, 2.6, 2.7, 3.0 

Pale, many cracks, wet inside, chips slightly melted, easy to pull apart.

Replacing baking soda with baking powder

5.9, 6.1, 6.4, 6.6, 6.7, 6.9

1.5, 1.7, 1.8, 1.9, 2.1, 2.2

Lightly brown, 

1 teaspoon baking soda, 1 teaspoon baking powder

6.9, 7.1, 7.3, 7.4, 7.6, 7.6 

1.6, 1.6, 1.7 1.8, 1.9, 2.0

Brown, Chewy, 

4 teaspoons baking soda

6.8, 7.0, 7.1, 7.3, 7.4, 7.6

1.9, 2.0,  2.1 ,2.1, 2.3, 2.5

Pale, many cracks

4 teaspoons baking powder

5.9, 6.0, 6.2, 6.2, 6.3, 6.5

2.0, 2.2, 2.4, 2.5, 2.7 2.8


2 tablespoons baking soda

6.9, 7.0, 7.1, 7.3, 7.4

2.6, 2.7 2.8, 3.0, 3.1

Rise a lot



2 teaspoons baking soda(Height)- 1.8, 1.9, 2.2, 2.2, 2.3, 2.4 

Mean- 2.13333333333

Median- 2.2

Mode- 2.2

2 teaspoons baking soda ( Width )- 7.3, 7.5, 7.6, 7.7, 7.7, 7.8

Mean- 7.6

Mode- 7.7

No Baking Soda or Baking Powder (Height)-2.3, 2.4, 2.4, 2.6, 2.7, 3.0 

Mean- 2.56666666667

Median- 2.5

Mode- 2.4

No Baking Soda or Baking Powder ( Width )- 4.2, 4.3, 4.4, 4.4, 4.6, 4.7

Mean- 4.0

Median- 4.4

Mode - 4.4

2 teaspoons baking powder (Height) - 1.5, 1.7, 1.8, 1.9, 2.1, 2.2

Mean- 1.86666666667

2 teaspoons baking powder ( Width ) -  5.9, 6.1, 6.4, 6.6, 6.7, 6.9

Mean- 6.43333333333

Median- 6.5

1 teaspoon baking soda and 1 teaspoon baking powder ( Height )- 1.6, 1.6, 1.7 1.8, 1.9, 2.0

Mean- 1,76666666667

Mode- 1.6

1 teaspoon baking soda and 1 teaspoon baking powder ( Width )- 6.9, 7.1, 7.3, 7.4, 7.6, 7.6 

Mean- 7.31666666667

Mode- 7.6

4 teaspoons baking soda ( Height )- 1.9, 2.0,  2.1 ,2.1, 2.3, 2.5, 

Mean- 2.15

Median- 2.1

Mode- 2.1

4 teaspoons baking soda ( Width )- 6.8, 7.0, 7.1, 7.3, 7.4, 7.6

Mean- 7.2

Median- 7.2


4 teaspoons baking powder ( Height )- 2.0, 2.2, 2.4, 2.5, 2.7 2.8

Mean- 2.43333333333

4 teaspoons baking powder ( Width )- 5.9, 6.0, 6.2, 6.2, 6.3, 6.5

Mean- 6.18333333333

Median- 6.2

Mode- 6.2

2 tablespoons baking soda ( Height )- 2.6, 2.7 2.8, 3.0, 3.1

Mean- 2.84

Median- 2.8

2 tablespoons baking soda ( Width )-6.9, 7.0, 7.1, 7.3, 7.4    Mean- 7.1      Median- 7.1





When you add more baking powder the cookie rises more, and has a smaller width. When you add no baking soda or baking powder, It rises more, and has a lot smaller width. When you do a normal batch of cookie, it looks normal, so you should use that amount. My hypothesis was both correct and incorrect. I thought that the more baking powder you had, the more the cookie would rise and grow. When I added more baking powder it rose, but did not grow in width. None of the cookies I made collapsed, because they did not rise enough. When I changed the material, It did not make a difference, but the amount of it did.





This project helps the real world because bakers and chefs can know how much baking soda and powder to use in chocolate chip cookies.  Most people don’t have the time or supplies to do this experiment, so they can just look at my results! This experiment will help people not waste time and materials. This experiment will help me in the future to know how much works the best, and if my cookies go wrong I know what happened. It also helps normal people who want a chocolate chip cookie make their cookies nice and chewy, because who doesn't love a chocolate chip cookie?


Sources Of Error

Sources of Error


The first way I went wrong is by doubling the eggs. On my first try I accidentally doubled the eggs. The batter came out very runny and the cookies melted in the oven. They ended up being very flat and burned. Another thing that may have gone wrong was the softness of my butter. The recipe calls for room temperature butter, but everytime I used different methods to melt the butter. I used the microwave to melt the butter, but sometimes it melted more than other times. Another error was leaving the batter out for a period of time. For some batches I left the batter out while the oven preheated.



Throughout this experience many people helped me. My parents helped me very much by supervizing me bake, and helping get supplies. My teacher helped me by giving me this amazing opourtunity and helping me throughout this experience. My friends also helped me by encouraging me and pushing me to do better. They also gave me suggestions. Thank you to all the people who helped me!


No Log Book Provided