the effect of temperature on atoms
DESCRIPTION
The effect of temperature on atoms. Item format: What happens to the [ ] of the atoms of a substance when the temperature is increased? A. The [ ] increases B. The [ ] decreases C. The [ ] stays the same where [ ] is Distance between Speed Number Size Mass. - PowerPoint PPT PresentationTRANSCRIPT
Project 2061: Student Assessment
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The effect of temperature on atoms
Item format:
What happens to the [ ] of the atoms of a substance when the temperature is increased?
A. The [ ] increases
B. The [ ] decreases
C. The [ ] stays the same
where [ ] is
1. Distance between2. Speed3. Number4. Size5. Mass
Project 2061: Student Assessment
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% correct vs. grade
The % of “not sure” responses is higher for 6th grade.
Approximately 50% of 6th grade students were not familiar with atoms.
Student were taught atoms and molecules in 7th grade.
0%
10%
20%
30%
40%
50%
60%
70%
6 7 8 9Grade
% c
orr
ect
Distance NumberSpeed SizeMass
Project 2061: Student Assessment
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Student data for item about distance between atoms
Distance between atoms ____ with increasing temperature
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
70.0%
80.0%
90.0%
INCREASES decreases stays the same Not Sure
6th grade 7th grade 8th grade 9th grade
Very few students believed that the distance would stay the same.
Misconception that distance decreases was well represented.
Project 2061: Student Assessment
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Student data for item about mass of atoms
The mass of the atoms ____ with increasing temperature
0.0%
10.0%
20.0%
30.0%
40.0%
50.0%
60.0%
increases decreases STAYS THE SAME Not sure
6th grade 7th grade 8th grade 9th grade
Misconception that mass decreases with increasing temperature drops off with increasing grade.
9th graders showed a preference for the mass increasing with increasing temperature.
Project 2061: Student Assessment
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Student data from pilot testing in 3 different school districts (grades 6-9)
The % “not sure” is significant for all items.
Students did the best on the speed item (45%).
Students did the worst on the mass item (23%). Student equally split between all answer choices.
Misconception that distance between atoms decreases with increasing temperature is held by a large %.
The misconceptions for number, size, and speed were all represented.
# students increases decreases stays the same not sure
Distance 147 30% 21% 9% 40%
Speed 154 45% 12% 14% 30%
Number 151 19% 16% 33% 32%
Size 154 18% 16% 30% 36%
Mass 158 22% 23% 23% 32%
Project 2061: Student Assessment
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Connecting the macro-scale phenomenon with the molecular explanation
Answer Choices Version 1:A. Even though you cannot see it, the pan gets a tiny bit smaller because the iron atoms decrease in size. B. Even though you cannot see it, the pan gets a tiny bit smaller because the distance between iron atoms decreases.C. Even though you cannot feel it, the pan gets a tiny bit heavier because the iron atoms increase in mass.D. Even though you cannot feel it, the pan gets a tiny bit heavier because the number of iron atoms increases.
Answer choices Version 2:A. The iron atoms get heavier.B. The iron atoms decrease in size.C. The number of iron atoms increases.D. The distance between iron atoms decreases.
Stem:After cooking breakfast, a cook places a hot iron frying pan on the counter to cool. What happens as the iron pan cools?
Project 2061: Student Assessment
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Student data from pilot testing - (Grades 7-9)
Is Answer Choice Correct?
A (size) B* (distance) C (mass) D (number) % Correct
Yes 2 6 6 6 14%
No 23 19 12 12
Not Sure 12 12 19 19
Is Answer Choice Correct?
A (mass) B (size) C (number) D*(distance) % Correct
Yes 2 6 0 22 68%
No 23 18 23 2
Not Sure 6 7 8 7
Version 1: Linking macro/molecular: 38 students
Version 2: Molecular only: 31 students
Project 2061: Student Assessment
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Sample Student Responses to Version 1 answer choices
Answer choice A: No "Because if every time you cooked with an iron pan and the atoms got smaller in a couple of years you would not have an iron pan anymore would you."
Answer choice A: No "Because I don't think a pan can decrease its size without being broken."
Answer choice B: No "A pan cannot get smaller"
Answer choice B: No "No because the pan cannot get a tiny bit smaller."
Answer choice C: Not Sure "Its possible it could get heavier by atoms increase in mass but I'm not sure."
Answer choice D: Not Sure "This answer makes more sense after I eliminated the others"
Project 2061: Student Assessment
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Sample Student Responses to Version 2 answer choices
Answer choice A: No because “the iron atoms don’t get heavier when cooled down.”
Answer choice A: No because “atoms cannot increase in mass, or get ‘heavier’.”
Answer choice B: Yes “because they’re cooling so the size would decrease.”
Answer choice C: No because “temperature won’t create new molecules.”
Answer choice D: Yes “because since the temperature is cooling the iron atoms come closer together.”
Answer choice D: Yes because “the atoms slow down and get closer together.”
Project 2061: Student Assessment
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Expansion of a solid – Concrete sidewalksAM46-4Most sidewalks made out of solid concrete have spaces between the sections as shown in the diagram below. What happens to the width of the spaces during a hot day in the summer and why?
A. The spaces get wider because the concrete shrinks.B. The spaces get narrower because the concrete expands.C. The spaces stay the same because the concrete does not shrink or expand.D. Some spaces get narrower and some get wider because some concrete expands and some concrete shrinks.
Project 2061: Student Assessment
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Student data from pilot testing (85 students, grades 7-9)
Is Answer Choice Correct?
A (shrinks)
B* (expands)
C (neither)
D (both)
% Correct
Yes 12 17 32 11 18%
No 53 44 28 49
Not Sure 19 23 23 24
Project 2061: Student Assessment
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Sample student responses Answer choice A: Yes, because “concrete expands when its cold” Answer choice A: Yes, because “when it gets hot things shrink.” Answer choice B: Yes, “the concrete and other objects expand when they are
heated.” Answer choice C: Yes because “concrete don’t move or do anything except
break” Answer choice C: Yes, “the concrete can't get wider or shrink because it is a
solid" Answer choice C: Yes because “concrete is a solid that is hard and can’t
change shape.” Answer choice D: No, because “concrete’s shape or size isn’t affected by
heat.” Answer choice D: Yes, “because it all depends on what concrete you use.” Answer choice D: Yes, “because some concrete expand or shrink.” Answer choice D: No, “because concrete can’t do both at the same time.” Answer choice D: No, because “all the concrete has to do the same thing
because it is the same substance under the same conditions.”
Project 2061: Student Assessment
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Movement of molecules
In which of the following are the atoms or molecules NOT moving?
A. A solid wooden table
B. Liquid water in a glass
C. Air when there is no wind
D. All of the atoms or molecules of these materials are moving.
Project 2061: Student Assessment
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Student data from pilot testing – (38 students, grades 7-9)
Is Answer Choice Correct?
A(wood table)
B (water)
C (air)
D* (all moving)
% Correct
Yes 19 0 1 14 37%
No 14 34 29 18
Not Sure 3 2 6 4
Project 2061: Student Assessment
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Sample student responses
Answer choice A: Yes “because in a solid atoms have no room to move.”
Answer choice A: Yes “because it is solid and nothing can be inside it moving.”
Answer choice B: No “because atoms and molecules move through liquid water in a glass.”
Answer choice B: No because “molecules have more space to move around in and move faster.”
Answer choice C: No because “the air molecules move very freely.”
Answer choice C: No because “atoms in the air move even if there is no wind.”
Answer choice D: Yes because “all molecules move all the time.”
Answer choice D: No “because wood does not have molecules.”