Question

practice: scientific method
read each scenario and answer the questions to the right.
maggie loves fresh brownies, and her grandma told her if she places a piece of bread in the storage container with the brownies, the brownies will stay fresh and moist longer. maggie decides to test this idea. she bakes a batch of betty crocker brownies. she places 6 brownies in 6 individual tupper - ware containers. each brownie is the same size and placed in the same location. she adds a piece of bread to three of the brownie containers, and leaves the other three alone. each day for 3 weeks she measures the moistness of the brownies, and records her results.
alex wants to grow some flowers for his wife, but isnt sure which flowers will grow best in the soil in their yard. he goes to lowes and buys hydrangeas, roses, daisies, and tulips. he sections off the soil into four equal parts and plants each type of flower in their own section. all flowers receive the same amount of sunlight throughout the day and he waters them all the same amount and at the same time daily. he records the growth of the flowers once a week for a month.
abbey always gets zits on her chin and she cant figure out the best method to get rid of them. she decides to test several products to see which clears her face up fastest: washing with soap and water, washing with an acne face wash from the pharmacy, and washing her face with organic oils. for one week she just washes her face with water. the next week she washes every day with soap and water. the following week she uses the acne wash, and the last week she uses the organic oils. each week she records the number of zits she has on her chin at the end of the day.
jenny loves to chew gum, but hates losing the flavor. she normally chews juicy fruit, but she wants to know if there is another type of gum that holds the flavor longer. she buys 4 different packs of gum, one of them being her normal juicy fruit. every day after lunch she picks one piece of gum and chews it until it loses flavor. she times how long it takes for the gum to lose flavor, and records the time. she chews the same type of gum every day until she has used up the pack, and finds an average time for how long the flavor lasted. then she starts chewing a new type of gum, and continues until all 4 types have been tested.

1. independent variable:
2. dependent variable:
3. hypothesis:
4. control group:
5. experimental group:
6. constants:
7. independent variable:
8. dependent variable:
9. hypothesis:
10. control group:
11. experimental group:
12. constants:
13. independent variable:
14. dependent variable:
15. hypothesis:
16. control group:
17. experimental group:
18. constants:
19. possible threats to accuracy of results?
20. independent variable:
21. dependent variable:
22. hypothesis:
23. control group:
24. experimental group:
25. constants:
26. possible threats to accuracy of results?

Explanation:

Maggie's Brownies Experiment

Step1: Identify independent variable

The presence or absence of bread in the brownie container.

Step2: Identify dependent variable

The moistness of the brownies.

Step3: Formulate hypothesis

If a piece of bread is placed in the brownie container, the brownies will stay fresh and moist longer.

Step4: Determine control group

The three brownie - containers without bread.

Step5: Determine experimental group

The three brownie - containers with bread.

Step6: List constants

Size of brownies, location of containers, type of brownies (Betty Crocker).

Step1: Identify independent variable

The type of flower (hydrangeas, roses, daisies, tulips).

Step2: Identify dependent variable

The growth of the flowers.

Step3: Formulate hypothesis

There is a difference in the growth of hydrangeas, roses, daisies, and tulips in the soil of his yard.

Step4: Determine control group

There is no explicit control group as all flower types are being tested. But if we consider one type as a reference, it could be a default or common - knowledge type for that area (none specified here).

Step5: Determine experimental group

All four types of flowers (hydrangeas, roses, daisies, tulips).

Step6: List constants

Amount of sunlight, amount of water, watering time, soil type (same yard soil).

Step1: Identify independent variable

The type of face - washing product (water only, soap and water, acne face wash, organic oils).

Step2: Identify dependent variable

The number of zits on her chin.

Step3: Formulate hypothesis

One of the face - washing products (soap and water, acne face wash, organic oils) will clear up her zits faster than just washing with water.

Step4: Determine control group

The week when she washes her face with water only.

Step5: Determine experimental group

The weeks when she uses soap and water, acne face wash, and organic oils.

Step6: List constants

Time of day she washes her face, area of face (chin), duration of each treatment (one week).

Answer:

1. Independent variable: Presence of bread in the container
2. Dependent variable: Moistness of brownies
3. Hypothesis: If a piece of bread is placed in the brownie container, the brownies will stay fresh and moist longer
4. Control group: Brownies in containers without bread
5. Experimental group: Brownies in containers with bread
6. Constants: Size of brownies, location of containers, type of brownies

Alex's Flower - Growing Experiment