Primary Type: Lesson Plan
Status: Published
This is a resource from CPALMS (www.cpalms.org) where all educators go for bright ideas!
Resource ID#: 25443
Chemical and Physical Changes Lesson 3 of 4
During a physical change, particles at the microscopic level, re-arrange themselves, but no new substance is formed. During a chemical change,
particles are broken apart and the atoms are re-arranged into new particles, thereby forming a new substance.
Subject(s): Science
Grade Level(s): 8
Intended Audience: Educators
Suggested Technology: Document Camera,
Computer for Presenter, Computers for Students,
Internet Connection, Probes for Data Collection, LCD
Projector, Speakers/Headphones, Microphones, Adobe
Flash Player, Adobe Acrobat Reader, Microsoft Office,
Computer Media Player
Instructional Time: 2 Hour(s) 20 Minute(s)
Resource supports reading in content area: Yes
Freely Available: Yes
Keywords: microscopic , macroscopic, reactant, product, equation, atoms, molecules, particle, particulate
Resource Collection: FCR-STEMLearn Science - General
ATTACHMENTS
PrePost testChemical Physical change.pdf
Test items Project 2061 Physical and Chemical.docx
Chemical and Physical Change Mini assessment.docx
Culminating Assessment.doc
Hand boiler( Pulse) and candle predictions.docx
LESSON CONTENT
Lesson Plan Template: Learning Cycle (5E Model)
Learning Objectives: What will students know and be able to do as a result of this lesson?
The student will be able to differentiate between a physical and chemical change. Students will explain what is happening at the particulate level when a change in
matter occurs. Using these two goals, students will understand that in a physical change the particles of the substance are re-arranged while in a chemical change the
particles of the substance are broken apart and the atoms are re-arranged into a new arrangement, thereby forming a new substance.
Prior Knowledge: What prior knowledge should students have for this lesson?
Students should know how to differentiate between chemical and physical changes at the macro-level.
Students should know what an atom, a molecule, a physical property, and a chemical property are. At the macro-level, students should explain signs of physical
change vs. signs of chemical change.
Students should know that mass is neither created nor destroyed during the course of a chemical reaction( Law of Conservation of Mass).
Students should know that there are three states of matter: solid, liquid, and gas. (Tell students that the plasma state occurs in the sun and other stars).
Guiding Questions: What are the guiding questions for this lesson?
Hand Pulse:
page 1 of 4 1. When the glass is held at the bottom, what causes the liquid to rise?
2. What's happening at the molecular level? Make sure to draw the details and explain your diagram.
3. Is it a physical or a chemical change? What is your reasoning?
Candle and Bell Jar:
1. What is the reactant? What is a product?
2. What happens to the particles of the reactants during a chemical interaction? Is the change in the candle a chemical or a physical change? What is your reasoning?
Engage: What object, event, or questions will the teacher use to trigger the students' curiosity and engage them in the concepts?
Pulse Glass: Teacher will give each group a pulse glass. The Pulse Glass is made of thin glass and has a coiled neck and a bulb head and contains colored alcohol (BP
70 degrees Celsius). Students appreciate the movement of the liquid in a closed system and always think of the liquid as boiling. Hence, the Pulse Glass is also known
as the 'Hand Boiler'.
Safety measures: Safety goggles. Tell students that the Pulse Glass is thin and fragile, so they should not be squeezing the bottle. They should report any broken glass
to the teacher.
Burning a Candle Under a Bell Jar: Students will use an aluminum pan to burn a candle, covering it with a bell jar while it burns.
Safety measures: Make sure that students conduct the experiment in the presence of an adult. Hair must be tied off and swept to the back. Students must be wearing
their safety goggles.
Explore: What will the students do to explore the concepts and skills being developed through the lesson?
Exploration A: Students will work in groups of 4. Students will hold the Pulse Glass in their palms and will observe the movement of the liquid recording their
observations thereafter. Students will draw diagrams to explain the liquid’s behavior at the particulate level.
Exploration B: Students will record the properties of the candle before and after they light it. Students will then observe the burning of the candle and record their
observations at the particulate level.
Explain: What will the students and teacher do so students have opportunities to clarify their ideas, reach a conclusion or
generalization, and communicate what they know to others?
Pulse Glass: Students will share their reports and diagrams with the class using whiteboards.
Burning of a candle: Students will use a whiteboard to explain their understanding of what happened to the candle while it was burning.
In both explorations, students will defend their arguments with evidence.
Afterwards, students will watch a Nova video clip, {On Fire}, provided in the link below to deepen their understanding of what happens at the micro/particulate level
when a candle burns.
http://www.pbs.org/wgbh/nova/cigarette/onfire.html
Students will explain at the particulate level what happens to the rusting nail- (See formative assessment). Students will revise their answers and change their sticky
notes to reflect their understanding where appropriate.
Elaborate: What will the students do to apply their conceptual understanding and skills to solve a problem, make a decision,
perform a task, or make sense of new knowledge?
Students will be given word equations and will be asked to apply their understanding by making models of the reactions using gum drops and toothpicks. Using models
could be a good way to establish a view of the world at the particulate level; this has always been challenging for students.
Afterwards, each student will create two brochures:
1. Trace the journey of a water molecule in Nature. Explain the physical change at the particulate level as the water changes its state. Make sure to explain this
physical change in terms of energy. Describe the forces of attraction among particles, particles arrangement, movement, and kinetic energy. Students will be given the
choice to pick their routes: transpiration, typical water cycle, runoff, etc.
2. Trace the journey of a burning candle at the particulate level.
Summative Assessment
Students will be given a Pre/Post test at the beginning and end of the lesson. Credit of this assessment will go to
http://chemistry.muohio.edu/yezierski/assessment.pdf
Instructions for this assessment can be found in the uploaded attachments.
Also, before the post assessment students will be given the Chemical and Physical Change mini-assessment (4 questions). The questions of this mini-assessment
are designed using atom models (drawings) to represent elements or compounds in an equation. Students will decide if the change is chemical or physical.
Credit for the 4 question quiz: American Association for the Advancement of Science, Science Assessment website, printed with permission.
http://assessment.aaas.org/pages/home
Both the mini-assessment and the pre/post-test and assessment are based on using common misconceptions as test distracters. This will be very useful to elicit
further misconceptions or preconceptions that students still hold.
Use post-test and the culminating assessment at the very end, namely after Chemical and Physical Changes Lesson 1 of 4. You will find the attachments of these
assessments in the Uploaded Files.
Formative Assessment
page 2 of 4 The teacher will give the students "The Rusty Nails" formative assessment probe- Keeley, P, Eberle, F, and Farrin, L (2005) - "Uncovering Student Ideas in Science- 25
Formative Assessment Probes" Volume I-NSTA Press, Arlington, Virginia.
The purpose of this probe is to elicit students' ideas about a common chemical change. Students will pick their answer (A, B, or C) and write their reasoning. Each
student will take a sticky note to place his answer under the letter he/she chose. The teacher will create a bar graph (Sticky notes bar graph- Keeley Page 75
Formative assessments Classroom Techniques (FACTS) – to monitor student’s progress and how their ideas are changing over the length of the lesson. Every time
students’ idea changes, the student will use a different sticky note.
Feedback to Students
The teacher will be listening to the students' discussions, hearing their ideas, looking at their diagrams, and prompting them to participate. The teacher will take notes
on a clip board or a portable keyboard as she/he moves around, listening to the group discussions. The teacher will compile these notes into a word document per
team/table color/group to be presented to the class using a ceiling projector, document camera, or the whiteboard. The teacher will try, firstly, to allow the students
to give feedback to each other in a class-wide discussion. The teacher will then fill in for any weaknesses in the discussion as he /she interacts with each group, giving
more detailed feedback. Students will utilize the new information to shape their thinking.
ACCOMMODATIONS & RECOMMENDATIONS
Accommodations:
- Provide students with special needs with ready-made charts to record their observations.
- Use visuals and steps to explain investigations that students will do.
- Use group assignment
- Paraphrase and repeat instructions
- Use colors and underline science vocabulary
Challenge the gifted kids to create their own chemical reactions at the particulate level. Provide them with more literature about matter. Or, challenge them to come
up with a futuristic vision of a reaction that can yield energy Eco-friendly by-products
Extensions:
Read " Researchers Capture First-Ever Image of Atoms Forming a Molecule" article at http://www.sciencedaily.com/release/2012/03/120307132216.htm
Read “The Stories of Science­Newton at the Center” chapters: 19, 20, 23­28.
Hakim, J (2005): “The Stories of Science­Newton at the Center" Smithsonian Books, Washington and New York.
Suggested Technology: Document Camera, Computer for Presenter, Computers for Students, Internet Connection, Probes for Data Collection, LCD Projector,
Speakers/Headphones, Microphones, Adobe Flash Player, Adobe Acrobat Reader, Microsoft Office, Computer Media Player
Special Materials Needed:
- Revise Lab safety rules
- Safety Goggles
- Fire Extinguisher
- Lab Aprons
- 2 Hand Boilers per group
- Gum drops candy or modeling clay
- Tooth picks
- Aluminum foil pans, matches (or lighter), bell jars (or large glass beakers)
- Markers, pencils, construction papers (copier papers are fine)
Further Recommendations:
This lesson is number 3 in a series of 4 lessons about chemical and physical changes. Make sure to read over lessons 1 and 2 in this series before you implement this
lesson. Make sure to read the different types of assessments first (formative, educative, and summative). Copies of the Chemical and Physical pre/post test, the
Chemical and Physical mini-assessment, and the culminating assessment can be found by clicking on attachments in the Uploaded Files tab.
Be advised that the Pre-test is meant to be given before Chemical and Physical Changes Lesson 1 of 4. Both the post-test and the culminating assessment are meant
to be given as summative assessments at the end of Chemical and Physical Changes Lesson 4 of 4. The mini-assessment must be given as a summative assessment
after Chemical and Physical Changes Lesson 3 of 4.
Additional Information/Instructions
By Author/Submitter
This lesson is the third in a series of four lessons:
Chemical and Physical Changes Lesson 1of 4
Chemical and Physical Changes Lesson 2 of 4
Chemical and Physical Changes Lesson 3 of 4
Chemical and Physical Changes Lesson 4 of 4
It is recommended to give the culminating assessment and the Chemical and Physical post-test at the end of Chemical and Physical Change Lesson 4 of 4 as summative
assessments to assess students' learning.
page 3 of 4 SOURCE AND ACCESS INFORMATION
Contributed by: Fadia Ahmed Hussien
Name of Author/Source: Fadia Ahmed Hussien
District/Organization of Contributor(s): Orange
Is this Resource freely Available? Yes
Access Privileges: Public
License: CPALMS License - no distribution - non commercial
Related Standards
Name
SC.8.P.9.2:
Description
Differentiate between physical changes and chemical changes.
page 4 of 4