A Standards-Based
Physical Science Lesson
Designed by Marian Furey and Judy Rosenbaum
Flory Academy of Sciences and Technology
Fruit and Tea Punch
Testing for Iron
Teacher’s Guide
This lesson is designed to accommodate grades three and five physical science
standards.
Lesson Description: Scientific Method to test for iron in different fruit juices
Background:
One way to see a chemical reaction is to watch a clear solution become cloudy as
solid particles (precipitates) form. Certain chemicals in tea react with iron
compounds in fruit juices to form precipitates.
Standards:
Grade 3:
Physical Sciences 1.g – Students know that when two or more substances are
combined, a new substance may be formed with properties that are different
from those of the original materials.
Investigation and Experimentation 5.a – Students will repeat observations to
improve accuracy and know that the results of similar scientific investigations
seldom turn out exactly the same because of differences in the things being
investigated, methods being used, or uncertainty in the observation.
5.c – Students will use numerical data in describing and comparing objects,
events, and measurements.
5.d – Students will predict the outcome of a simple investigation and compare
the result with the prediction.
5.e – Students will collect data in an investigation and analyze those data to
develop a logical conclusion.
Language Arts: Written and Oral English Language Conventions Sentence
Structure
1.1 Students will understand and be able to use complete and correct declarative,
interrogative, imperative, and exclamatory sentences in writing and speaking.
Grade 5:
Physical Sciences 1.a – Students know that during chemical reactions the atoms
in the reactants rearrange to form products with different properties.
Investigation and Experimentation
6.b – Students will develop a testable
question.
6.g – Students will record data by using appropriate graphic representations
(including charts, graphs, labeled diagrams) and make inferences based on those
data.
6.h – Students will draw conclusions from scientific evidence and indicate
whether further information is needed to support a specific conclusion.
6.i – Students will write a report of an investigation that includes conducting
tests, examining evidence, and drawing conclusions.
Vocabulary to introduce/review:
chemical change: a change that forms different kinds of matter
data: facts collected
precipitates: solid particles that form in a solution as a result of a chemical change
(reaction)
Materials:
*2 cups of strong tea
*an assortment of fruit juices, including canned and bottled juices, red juices,
pineapple juice, and prune juice
*juice glasses or test tubes
*pen and paper
* Student Guide, Data sheet, Science Lab Write-Up form (2 styles provided)
Scientific Question: (as opening)
TTW ask: Which fruit juices contain iron?
Procedure:
1. Prepare and distribute science lab write up, student guide, and data sheet
for each student. TLW begin hypothesis with “I think that…”
2. Instruct/assist students in: setting out a row of small glasses, (or test tubes)
putting about an inch of tea in each glass; labeling glasses for each juice to
be tested.
3. About an inch of juice will be added to each glass of tea. Observe
cloudiness. Designate forming of a precipitate with a plus (+) sign next to
the name of juice on data sheet. Designate with a minus (-) sign if mixture
remains clear. Use a question mark if uncertainty exists, and test again.
Some juices are cloudy to begin with, so make sure that a new precipitate
forms by comparing the tea mixture with a plain sample of juice.
Observations: Which fruit juices contain iron? Do canned juices contain more
iron than bottled juices?
Outcome/Conclusion: TLW state his/her result as “My hypothesis was…” and
complete lab write-up form.
According to a table of nutrition composition (vitamins, minerals, fats, proteins,
etc.) in food, the juices that contain the most iron are red juices, pineapple juice,
and prune juice. Did our outcome agree?
Completion: At the end of the experiment, pour all the mixtures into one pitcher.
Students can taste to see if they would like to add any more of a particular juice.
Serve with a treat!
Teacher Resources:
1. Cobb, Vicki Science Experiments You can Eat
2. Cooper, Christopher Matter
Name ___________________________
Fruit and Tea Punch
Testing for Iron
Student Data Page
FRUIT JUICE
TEST RESULT
Name ___________________________
Fruit and Tea Punch
Testing for Iron
Student Guide
Vocabulary:
chemical change: a change that forms different kinds of matter
data: facts collected
precipitates: solid particles that form in a solution as a result of a
chemical change (reaction)
Procedure:
1. Set out a row of small glasses or test tubes. Put about an inch of
tea in each glass. Label glasses for each juice to be tested.
2. Fill out your data sheet with the types of juices you are testing
and begin your Science Lab Write Up
3. About an inch of juice will be added to each glass of tea.
Observe cloudiness. If a precipitate forms, put a plus (+) sign
next to the name of juice on your data sheet. If the mixture
remains clear, put a minus (-) sign. If you are not sure, put a
question mark (?) on your data sheet and repeat the test. Since
some juices are cloudy to begin with, make sure that a new
precipitate forms by comparing the tea mixture with a plain
sample of juice.
Observations: Which fruit juices contain iron? Do canned juices
contain more iron than bottled juices?
Completion: Use your Science Lab Write Up to make your written
report/conclusions.
Name ___________________________
Science Lab Write Up
Question_____________________________________________________
_____________________________________________________________
Hypothesis___________________________________________________
_____________________________________________________________
Materials_____________________________________________________
_____________________________________________________________
Procedure:
Results_______________________________________________________
_____________________________________________________________
Conclusion___________________________________________________
_____________________________________________________________
_____________________________________________________________
Name ___________________________
Science Lab Write Up
Question_____________________________________________________
_____________________________________________________________
Hypothesis___________________________________________________
_____________________________________________________________
Materials_____________________________________________________
_____________________________________________________________
Procedure:
Results_______________________________________________________
_____________________________________________________________
Conclusion___________________________________________________
_____________________________________________________________
_____________________________________________________________