How many variables are in an experiment? Name the variables?
3
Tested- what we change
Measured- what we are measuring
Control- what we keep the same
A student claims that “plants grow better when they are talked to.”
How could you design an investigation to test this claim, and what evidence would you need to decide if the claim is true? Explain your reasoning.
Student answer may vary
What is the difference between balanced and unbalanced forces
Student answers may vary
Balanced=equal
Unbalanced=unequal
Which change is MOST affected by temperature?
A. Breaking a stick in half
B. Melting ice into water
C. Cutting paper into pieces
D. Mixing sand and salt
B. Melting ice into water
Ripping paper is a ______ change
Burning paper is a ______ change
Physical
Chemical
Which of the following is NOT an experiment?
A. Measuring how fast water evaporates at different temperatures.
B. Watching clouds and recording their shapes.
C. Testing which paper towel absorbs the most water.
D. Comparing how magnets attract different metals.
B. Watching clouds and recording their shapes
You are not controlling or testing anything
Which question is a testable question?
A) Why is the freezer kept at 0 degrees Fahrenheit?
B) Would cold water or hot water boil faster?
B) Would cold water or hot water boil faster?
The less mass an object has, the _______________ effect a force has on that object.
Greater
Which temperature will melt ice the fastest?
A) -10 C (14 F)
B) -30 C (-22 F)
C) 15 C (59 F)
D) 30 C (86 F)
D 30 C (86 F)
What is the best tool for separating iron filings from sand?
A) A mesh wire (sieve)
B) Tweezers (forceps)
C) Magnet
D) Magnify glass and tweezers
C) Magnet
Iron is magnetic
This is a testable question:
Will salt water freeze faster or slower than fresh water?
What is being tested, measured and controlled.
Tested: Fresh water and Salt water
Measured: How fast it takes to freeze
Controlled: Salt
Which statement is an observation?
A. The liquid is clear and has no smell.
B. The liquid will taste sweet.
C. The liquid is probably water.
D. The liquid will freeze quickly
A. The liquid is clear and has no smell.
The others are making inferences/ predictions
What are the different types of forces? And act it out!
Push
Pull
Gravity
Magnetism
Friction
Why does it take longer for a piece of ice to melt in cold water than hot water?
Since the water is higher (hot) it melts the ice faster.
Students answers may vary
Two objects have the same volume but different masses. What does this tell you about the objects?
A. They are made of the same material.
B. They have different amounts of matter.
C. They have the same weight.
D. They have the same color
B. They have different amounts of matter.
A student says, “Salt will dissolve faster in hot water than in cold water.” What should the student do to make this a scientific explanation?
A. Ask friends if they agree
B. Look at pictures of salt in water
C. Guess what will happen
D. Test the idea and record results
D. Test the idea and record results
A scientist claims that a new medicine works better than the old one. What must the scientist provide to support this claim?
A. Evidence from experiments and observations
B. Opinions from other scientists
C. A strong belief that the medicine works
D. A prediction about future results
A. Evidence from experiments and observations
. Bianca’s family is cleaning the garage. Bianca pushes an empty box to the shelves and fills the box with materials to donate. Which statement describes what will happen when Bianca pushes the box to the car?
A. The box will be easier to move because it has more mass.
B. The box will be easier to move because it needs more force now.
C. The box will be harder to move because it has more mass.
D. The box will be harder to move because it needs less force now.
C
More mass needs more force to move
Gyleen and Kyli were making Kool-Aid. Gyleen said that they do not have to stir the mixture in order for the powder to fully dissolve. Kyli said that they have to stir the powder in order for it to fully dissolve. Who is correct?
Kyli- you have to stir in order for the powder to fully dissolve.
Which observation BEST shows that a chemical change has occurred?
A. A piece of metal feels hot
B. A liquid turns into a gas
C. A solid turns into a powder
D. A gas is produced when two substances mix
D. A gas is produced when two substances mix
A scientist observes birds in a park and records how many visit each type of tree. What type of scientific investigation is this?
A. Experiment
B. Observation
Observation, you are only watching the birds go to different trees
Which student did NOT write an observation?
A. Angel – Each box takes up the same amount of space on the shelves.
B. Zavier – The box with the books 13kilograms mass.
C. Cade – The box with the pillows should have had more in it.
D. Roberta – The box with the writing tools was 3 kilograms heavier than the science tools.
C
Key word is should
A student notices that a soccer ball rolls farther on a smooth gym floor than on a grassy field.
Why does this happen, and how would the distance change if the ball were rolled on sand? Explain your reasoning.
Gym floor has less friction than grass (student answer may vary)
Samuel and Norre was making hot chocolate with real chocolate. Samuel used big chunks of chocolate, while Norre used small pieces. They both used hot water and stirred. Who's chocolate will dissolve the fastest?
Norre because she used small pieces
Imagine you are given a mixture of sugar and water. After leaving it in a warm place for several days, you notice bubbles forming and a sour smell.
Explain what type of change occurred, why do you think this happened, and how you could design an investigation to confirm your explanation.
Chemical change
Student answer may vary