Focus Plan
Texarkana Independent School District
GRADING PERIOD: / IPC – 4th, Biology – 2nd,Chemistry – 2nd / PLAN CODE:
WRITER: / L. Petty / COURSE/SUBJECT: / 10th grade science
GRADE(S): / 10th / TIME ALLOTTED FOR INSTRUCTION: / 1½ hours
TITLE: / Times Are Changing
LESSON TOPIC: / Physical and chemical changes.
TAKS OBJECTIVE: / Objective 4
The student will demonstrate an understanding of the structures and properties of matter.
FOCUS TEKS AND STUDENT EXPECTATION: / 10.8 The student knows that changes in matter affect everyday life. The
student is expected to:
(A) distinguish between physical and chemical changes in matter such as
oxidation, digestion, changes in states, and stages in the rock cycle
SUPPORTING TEKS AND STUDENT EXPECTATIONS: / Objective 1: The student will demonstrate an understanding of the nature of
science.
10.1 The student, for at least 40% of instructional time, conducts field and
laboratory investigations using safe, environmentally appropriate, and
ethical practices. The student is expected to:
(A) demonstrate safe practices during field and laboratory investigations
10.2 The student uses scientific methods during field and laboratory
investigations. The student is expected to:
(A) plan and implement investigative procedures including asking
questions, formulating testable hypotheses, and selecting equipment
and technology
(B) collect data and make measurements with precision
(C) organize, analyze, evaluate, make inferences, and predict trends from
data
(D) communicate valid conclusions
CONCEPTS / ENDURING UNDERSTANDINGS/GENERALIZATIONS/PRINCIPLES
The student will understand that
Changes / Changes occur everywhere in the world around us.
Physical / Physical changes do not change the identify of the substance.
Chemical / Chemical changes change the way the atoms are arranged and create one or more new substances.
Indicators / A permanent color change, formation of a precipitate, heat change and gas or light being produced all indicate a possible chemical change.
I. SEQUENCE OF ACTIVITIES (INSTRUCTIONAL STRATEGIES)
A. Focus/connections/anticipatory set
As a warmup, have students list the 5 indicators that a chemical change has occurred. They should list
permanent color change, formation of a precipitate, heat change, gas or light produced.
B. Instructional activities
(demonstrations, lectures, examples, hands-on experiences, role play, active learning experience, art, music, modeling, discussion, reading, listening, viewing, etc.)
1. Lecture
Go over vocabulary list.
C. Guided activity or strategy
Show students a roll of magnesium ribbon and have them list 5 physical properties of the ribbon. (silver, thin,
flexible, metallic, long, coiled, etc.) Tear off a piece about 2 inches long. Ask students whether you have
made a physical or chemical change and have them explain how they know. (Physical, still the same
substance.) Hold the ribbon in a pair of tongs and use a lighter or burner to ignite the ribbon. Have students
describe what they see. (Bright light and smoke. Point out that you are holding it with tongs so heat is given
off also.) Have them describe what is left. (White, crumbly ash) Ask what type of change has occurred and
how they know. (Chemical because heat, light and smoke were given off. Also, there was a different
substance left at the end.)
D. Accommodations/modifications
Students requiring modifications may be given a completed vocabulary list.
E. Enrichment
Students requiring enrichment may be assigned vocabulary as homework the class period prior to the lab.
II. STUDENT PERFORMANCE
A. Description
Complete Lab Worksheet – Times Are Changing.
B. Accommodations/modifications
Students requiring modifications may be assigned a peer tutor.
C. Enrichment
Students requiring enrichment may be assigned as a peer tutor.
III. ASSESSMENT OF ACTIVITIES
A. Description
Grade Lab Worksheet – Times Are Changing.
B. Rubrics/grading criteria
Each question or section of question should count as 4 points. Any left blank or unanswered should have 4
points deducted for each one.
C. Accommodations/modifications
Students requiring modifications may need help or may need to be excused from answering the critical
thinking and application section of the lab.
D. Enrichment
Students requiring enrichment should answer all questions and may also be assigned to list more examples of
chemical changes.
E. Sample discussion questions
1. What are the 5 indicators that a chemical change has occurred? Heat change, gas or light being produced,
formation of a precipitate, permanent color change.
2. Sulfuric acid is poured onto a seashell. The liquid starts to bubble. Describe what type of change this is
and explain how you know. Chemical because gas is being produced.
3. A glass of ice is left out in the sun. Explain what type of change occurs and how you know. Physical,
because it is still H2O, just in a different phase. It can be refrozen to form ice.
4. Water seeping into cracks in large boulders eventually breaks the boulders down into smaller rocks.
Describe what type of change this is and explain how you know. Physical, it is still rock, just in smaller
pieces. This is part of the rock cycle.
IV. TAKS PREPARATION
A. Transition to TAKS context
1. What occurs as wood is burned in a fire?
(a) The wood undergoes physical change, becoming ash, smoke, and hot gases.
(b) Heat and light are physically changed into stored chemical energy.
(c) The wood undergoes chemical change and uses more energy than it releases.
(d) The wood undergoes chemical change, becoming ash, smoke, and hot gases.
2. An observant student notices that the electrical and telephone wires in front of her school seem to sag and
droop on very hot days. The same wires stretch tightly between poles during cold winter days. What is the
best explanation for the student’s observations?
(a) The increased temperature on hot days causes the metal in the wires to expand and become longer.
(b) The increased temperature on hot days causes the metal in the wires to increase in mass. This results in
them becoming heavier and sagging.
(c) The increased temperature on hot days causes the metal in the wires to undergo chemical changes that
results in them becoming longer.
(d) The lower temperatures on cool days slows chemical changes that take place in the wires. The slower
rate of chemical change results in the wires stretching tightly between poles.
B. Sample TAKS questions
Spring 2003
1. In the rock cycle, which of these is a chemical change involved with the formation of igneous rocks?
(a) Compression of sediments
(b) Heat loss from lava
(c) Subduction of plates
(d) Formation of minerals
Spring 2004
1. Which of the following is an example of a chemical change?
(a) Ice cracking
(b) Sugar dissolving
(c) Milk souring
(d) Lead melting
2. Which of these describes a pollution-producing process that involves only a physical change?
(a) Coal with a high sulfur content is burned, producing gases that cause acid rain.
(b) Chlorofluorocarbons are released, changing ozone in the upper atmosphere into oxygen.
(c) Hot wastewater is discharged into a lake, lowering oxygen levels in the water.
(d) Nitrogen oxide emissions combine with water vapor, producing nitric acid.
V. KEY VOCABULARY
chemical change
chemical property
physical change
physical property
precipitate
VI. RESOURCES
A. Textbook
None needed
B. Supplementary materials/equipment
Instructor’s Copy – Times Are Changing
Lab Worksheet – Times Are Changing
Transparency – Vocabulary
Instructor’s Copy Transparency – Vocabulary
MSDS Information
C. Technology
VII. FOLLOW UP ACTIVITIES
(reteaching, cross-curricular support, technology activities, next lesson in sequence, etc.)
A. Reteach
Go over the correct answers with students when they get their graded papers.
B. Next lesson is sequence
IPC and Chemistry – Reactions
Biology – Law of Conservation of Mass
VIII. TEACHER NOTES
Before lab:
1. Make copies of Lab Worksheet – Times are Changing so that everyone may have one.
2. Make 500 mL of HCl by diluting 43 mL of 12 M HCl.
3. Make .1 M AgNO3 by adding g of solid to a 100 mL volumetric flask and diluting to the mark.
4. Make sure students know that goggles need to be worn as long as there are chemicals at their table.
5. Go over and/or pass out MSDS information on HCl and AgNO3.
6. Make sure students know that the chemicals should be put into a waste beaker.
7. Make sure all bottles and chemicals are clearly marked.
During lab:
8. Make sure students keep their goggles on!
9. Make sure students are not pouring chemicals in the sinks.
10. Make sure students who handle chemicals wash their hands before leaving class.
11. Make sure students clean up their lab stations and wash the tables before they leave, even if they do not think
chemicals have spilled.