Lab Safety
You are heating a substance in a test tube. Which direction should the opening of the test tube point?
A. Toward yourself
B. Toward your partner
C. Away from everyone
D. Straight down
C. Away from everyone
Which part of CER directly answers the scientific question?
CLAIM (C)
A student says, “The candle flame is approximately 3 cm tall.” This is a(n):
A. Inference
B. Observation
B. Observation
A student changes the amount of sunlight plants receive and measures how tall the plants grow. What is the independent variable?
A. Plant height
B. Amount of sunlight
C. Type of plant
D. Amount the plant grows
B. Amount of sunlight
Your lab partner begins mixing two substances that the directions do not tell you to mix. What should you do?
A. Help them mix the substances
B. Tell them to stop and notify the teacher
C. Move to another table
D. Wait to see what happens
B. Tell them to stop and notify the teacher
Students test two types of soil. Plants in Soil A grow an average of 15 cm, while plants in Soil B grow an average of 9 cm. Which statement is evidence?
A. Soil A is better for plant growth.
B. Soil A must contain more nutrients.
C. Plants in Soil A averaged 15 cm and plants in Soil B averaged 9 cm.
D. Plants grow differently in different soils.
C. Plants in Soil A averaged 15 cm and plants in Soil B averaged 9 cm.
You walk outside and notice the sidewalk is wet. You say, “It must have rained earlier.” Which part is the inference?
The inference is when you say "It must have rained earlier." because you used what you observed to make a conclusion or claim.
A student tests whether water temperature affects how quickly an ice cube melts. What is the dependent variable?
A. Water temperature
B. Size of the container
C. Time it takes the ice cube to melt
D. Type of ice cube
C. Time it takes the ice cube to melt
When should safety goggles be removed during a lab that requires eye protection?
A. When your goggles become uncomfortable
B. When you finish your part of the experiment
C. When the teacher says it is safe to remove them
D. When you need to read the directions
C. When the teacher says it is safe to remove them
A student writes: “Objects with greater mass required more force to move. The 5 kg object required 20 N of force, while the 1 kg object required only 4 N.”
Which sentence is the claim?
Objects with greater mass required more force to move.
Which statement is an observation?
A. The dog is hungry.
B. The dog did not eat breakfast.
C. The dog is barking because it wants food.
D. The dog is barking.
D. The dog is barking.
A student wants to know whether the type of soil affects plant growth. She uses the same type of plant, same amount of water, and same amount of sunlight for every group. Those factors are:
A. Independent variables
B. Dependent variables
C. Controlled variables
D. Claims
C. Controlled variables
A glass container breaks during an experiment. What is the safest response?
Tell the teacher and stay away from the broken glass
What is missing?
Claim: Salt dissolves faster in warmer water.
Evidence: Salt dissolved in 25 seconds in hot water and 70 seconds in cold water.
________: Faster-moving water molecules in warmer water interact with the salt more frequently, helping it dissolve faster.
Reasoning
A student observes that a plant's leaves are drooping. What would be an inference based on that observation?
The plant may be dying and needs water.
A student wants to know whether the height of a ramp affects how far a toy car travels. Identify the independent and dependent variables.
A. IV = distance traveled; DV = ramp height
B. IV = ramp height; DV = distance traveled
C. IV = toy car; DV = ramp height
D. IV = distance traveled; DV = toy car
B. IV = ramp height; DV = distance traveled
Why is it important to read the entire lab procedure before beginning an experiment?
So you know what to expect and can perform the lab safely.
Give your BEST description of reasoning in a CER.
It explains how the evidence supports the claim using scientific ideas.
What is the biggest difference between an observation and an inference?
Observations describe what you notice or measure; inferences explain what those observations might mean.
A student wants to know whether water temperature affects how quickly sugar dissolves.
They use:
Which correctly identifies the variables?
A. IV: dissolving time; DV: temperature; Controls: sugar and water amount
B. IV: temperature; DV: dissolving time; Controls: water amount, sugar, and cup
C. IV: sugar; DV: temperature; Controls: dissolving time and cup
D. IV: water amount; DV: sugar; Controls: temperature and time
B. IV: temperature; DV: dissolving time; Controls: water amount, sugar, and cup