Scientific Theory Study Guide: ______

Scientific Theory Study Guide: ______

Name: ______Date: ______

1. / Linda is curious about how snowflakes form. Which of the following sentences is the best hypothesis for Linda to test?
A. / Why do snowflakes form?
B. / Snowflakes form when water freezes slowly.
C. / Something causes snowflakes to form inside
a cloud.
D. / Snowflakes are different from rain and sleet.
2. / Ali experimented to find out which freeze easier, fresh water or salt water. The steps of his experiment are shown below.

Fill two beakers with 250 mL of room-temperature fresh water
Dissolve 30 grams of salt in one of the beakers
Place both beakers in a freezer and observe which liquid freezes first

Which variable in this experiment is the independent variable?
A. / the type of beaker used to hold the water
B. / the amount of salt in each beaker of water
C. / the length of time it takes each beaker of water to freeze
D. / the type of salt added to one beaker of water
3. / Which of the following sentences gives the best instructions for formulating a hypothesis?
A. / Write a sentence that could be a possible answer to a question.
B. / Write a list of observations you have made on the subject.
C. / Write a step-by-step description of an experimental procedure.
D. / Write a question that you have about a natural phenomenon.
4. / A scientist has just finished a series of scientific investigations. He has analyzed the data and drawn conclusions. What should the scientist do next so that other scientists can find out about his work?
A. / communicate his results
B. / write a scientific theory
C. / start a new investigation
D. / repeat the experiment ten times
5. / Mario believes he has found the reason that some things glow in the dark while others do not. What is the most important thing he will need to do before his theory will be accepted by other scientists?
A. / Develop an online survey so people can vote on the accuracy of his theory.
B. / Write a book promoting his theory.
C. / Create a petition and ask everyone who believes in his theory to sign it.
D. / Develop and test experiments that can be repeated to prove his theory.
6. / Elliot wants to compare the density of four objectsto the density of water. Elliot knows that if an object sinks in water, it has a higher density than water and that if an object floats in water; it has a lower density than water.
Which of the following is a scientific investigation that Elliot could conduct to test the densities of the objects?
A. / Elliot could ask his teacher which object has the greatest density.
B. / Elliot could look up the densities of the objects in a textbook.
C. / Elliot could put the objects in water to see how much water they absorb.
D. / Elliot could put the four objects in water to see if they sink or float.
7. / Wendy did an experiment to see what color of flower butterflies are most attracted to. In the first experiment, Wendy found that most of the butterflies first went to the orange flowers. In her second experiment, she found that most of the butterflies first went to the red flowers. In the third experiment, she found that most of the butterflies went to yellow flowers.
What is the most likely explanation for this difference?
A. / Butterflies do not see color.
B. / The butterflies Wendy used were trying to confuse her.
C. / Butterflies like only orange flowers.
D. / Wendy made mistakes recording her observations during one of the experiments.
8. / Which of the following questions could best be investigated using a scientific experiment?
A. / How many lady bugs have ever lived?
B. / How many seeds are in an apple?
C. / How many pebbles are at the bottom of a river?
D. / Why are there insects on Earth?
9. / Gina set up an experiment to see if Supercell brand batteries last longer than store brand batteries. She put both kinds of batteries in similar flashlights, turned the flashlights on and recorded her observations.
What is a controlled variable in Gina’s experiment?
A. / The type of flashlight she used.
B. / Her observations and hypothesis.
C. / Amount of time it took each battery to stop working.
D. / The type of batteriesshe used.
10. / Which of the following characteristics must a hypothesis have?
A. / A hypothesis must predict a possible answer to the question.
B. / A hypothesis must always be correct.
C. / A hypothesis must be written in English.
D. / A hypothesis must be written as a question.
11. / Eddie set up a science experiment with plants. He bought three small tomato plants, all about the same size, and set them all on his window sill. He watered the first plant every day, the second plant every other day, and the third plant every third day, making sure to use the same amount of water each time. He planned to measure the height of each tomato plant after three weeks.
What was the independent variable in Eddie's experiment?
A. / the number of tomatoes produced
B. / how frequently the plants were watered
C. / the amount of sunlight received
D. / how tall the plants grew
12. / Which of the following is a good scientific question?
A. / What does an astronaut think about the atmosphere?
B. / How does stirring affect the rate at which a substance dissolves?
C. / How does the color of a plant affect whether it likes to be in the cold?
D. / What is the effect of the weather on the color of clothes my friend likes to wear?
13. / Which of the following is a scientific question that could be used to form a good hypothesis?
A. / How does temperature affect the growth rate of pea plants?
B. / What is the effect of the weather on a person's mood?
C. / How does the flavor of a candy affect its taste to people?
D. / What is the effect of one person's opinion on another person?

14. Which instrument measures mass?

ruler
graduated cylinder
beaker
balance scale

24. What lab instruments are represented below?

A.beaker; funnel; test tube

B.funnel; beaker; graduated syringe

C.beaker, test tube; graduated syringe

D.beaker; test tube; graduated cylinder

25.Greg's teacher tells the class that they will be doing an experiment in the laboratory today, and that the experiment will involve working with several chemicals. What should Greg do before beginning the experiment?

A. / make sure the lab area is clean
B. / listen to his teacher's instructions
C. / put on his safety goggles
D. / all of these

Use the following scenario to answer questions 27 - 29

James did an experiment to test the effect of temperature on the growth of a certain kind of plant. He recorded his observations in the table below.

Temperature of Area

Plant Growth

10°C

0 cm

15°C

1.2 cm

20°C

2.3 cm

25°C

1.9 cm

30°C

1.1 cm

27. What is the independent variable in James’s experiment?

A. Plant growth

B.Temperature

C.Amount of water

D.The kind of plants he used

28. What is the dependent variable in James’s experiment?

A. The kind of plants he used

B.Temperature

C.Amount of water

D.Plant growth

29. Which graph best represents the data in the table?

30. Which of the following statements is an inference?

A. The blue bird likes warm climate and therefore, it migrates south.

B. The blue bird is nests in a tree.

C. The blue birds does not migrate

D.The blue bird is migrating north

31. John observed that his plant grew 11 cm in seven days. He recorded his observation in his log.

What kind of observation did John make?

A.Quantitative

B. Lucrative

C.Qualitative

D.Argumentative

32. John also recorded in his log that the plant had narrow and wide leaves.

What kind of observation did John make?

A. Qualitative

B.Quantitative

C.Argumentative

D.Lucrative

33. What is the next logical step after you identify a question for a scientific investigation?

A.Plan for the independent, dependent and controlled variables.

B.Communicate your results

C.Develop a hypothesis

D. Research your topic