Lesson
Plan: Colloid
Education
Unit : Senior High School
School
Name : State Senior High School 4
Subject : Chemistry
Class / Semester : XII / Even Semester
Learning Materials : Colloid
Allocation of Time : 1x 45 minutes
I. Competence Standards : 5. Describe the system and the
properties of colloid and its application in daily life.
II. Basic Competence : 5.1 To classify the properties of colloid and
its application in daily life
III. Indicator
A.
Cognitive
1. Classify the types of colloid
systems based on dispersed phase and dispersing medium.
2. Describe the phenomenon of colloid
in daily life
B. Affective
Character
skills :
Show an appreciation of scientific attitudes such as .
honest, responsibility,curiousity, passionate about learning and open mindness.
IV. Learning
Objectives:
A.
Cognitive
1. After students do some
observations, students can classify the types of colloid systems based on
dispersed phase and dispersing medium.
2. Given some problems, students may
mention the role of colloid in cosmetics, foods, and pharmaceuticals.
B. Affective
Character
skills :
Show an
appreciation of scientific attitudes such as . honest, responsibility,
curiousity, passionate about learning
and open mindness.
V.
Learning Materials
Colloids
are mixtures whose particles are larger than the size of a molecule but smaller
than particles that can be seen with the naked eye. Colloids are one of three
major types of mixtures, the other two being solutions and suspensions. The
three kinds of mixtures are distinguished by the size of the particles that
make them up. The particles in a solution are about the size of molecules,
approximately 1 nanometer (1 billionth of a meter) in diameter. Those that make
up suspensions are larger than 1,000 nanometers. Finally, colloidal particles
range in size between 1 and 1,000 nanometers. Colloids are also called
colloidal dispersions because the particles of which they are made are
dispersed, or spread out, through the mixture.ypes of lloids
Colloids
are common in everyday life. Some examples include whipped cream, mayonnaise,
milk, butter, gelatin, jelly, muddy water, plaster, colored glass, and paper.
Every
colloid consists of two parts: colloidal particles and the dispersing medium.
The dispersing medium is the substance in which the colloidal particles are
distributed. In muddy water, for example, the colloidal particles are tiny
grains of sand, silt, and clay. The dispersing medium is the water in which
these particles are suspended.
Colloids
can be made from almost any combination of gas, liquid, and solid. The
particles of which the colloid is made are called the dispersed material. Any
colloid consisting of a solid dispersed in a gas is called a smoke. A liquid
dispersed in a gas is deferred to as a fog.
|
Dispersed
Material
|
Dispersed
in Gas
|
Dispersed
in Liquid
|
Dispersed
in Solid
|
|
Gas
(bubbles)
|
Not
possible
|
Foams: soda pop;
whipped cream; beaten egg whites
|
Solid
foams: plaster; pumice
|
|
Liquid
(droplets)
|
Fogs: mist;
clouds; hair sprays
|
Emulsions: milk;
blood; mayonnaise
|
butter;
cheese
|
|
Solid
(grains)
|
Smokes: dust;
industrial smoke
|
Sols and
gels: gelatin; muddy water; starch solution
|
Solid sol: pearl;
colored glass; porcelain; paper
|
Each
type of mixture has special properties by which it can be identified. For
example, a suspension always settles out after a certain period of time. That
is, the particles that make up the suspension separate from the medium in which
they are suspended and fall to the bottom of a container. In contrast,
colloidal particles typically do not settle out. Like the particles in a
solution, they remain in suspension within the medium that contains them.
Colloids
also exhibit Brownian movement. Brownian movement is the random zigzag motion
of particles that can be seen under a microscope. The motion is caused by the
collision of molecules with colloid particles in the dispersing medium. In
addition, colloids display the Tyndall effect. When a strong light is shone
through a colloidal dispersion, the light beam becomes visible, like a column
of light. A common example of this effect can be seen when a spotlight is
turned on during a foggy night. You can see the spotlight beam because of the
fuzzy trace it makes in the fog (a colloid).
VI.
Model
and Learning Method:
Model Learning: Learning Cycle 5E
Learning Method: Demonstration, discussion, tasks giving
VII.
Learning Activities
|
No
|
Teaching-Learning Activities
|
Allocation of
Time
|
|
A.
|
Introduction:
· Teacher starts
the lesson by greeting, prayer, checking the attendance and
cleanliness of classroom
Engagement phase
·
Teacher
demonstrates stirring detergent in
water
·
Teacher asks
students, “what happens after I stirred the detergent in water?” and “why
there is foam in there?”. to grow up the curiousity of the students.
·
Teacher asks
students to mention the other similar phenomenon which have been demonstrated
·
Students are
guided to relate the phenomenon with the learning material which will be
learn.
|
2 minutes
5 minutes
|
|
2.
|
Core activities
Exploration
Phase
·
Teacher asks some questions about colloid :
1. Can you explain about colloid?
2. Do you know 2 components of
colloid?
3. Please explain the types of
colloids?
4. Do you know what colloid types of
fog, butter,dust and whipped cream?
·
Teacher guide the student to discuss each other about the question and the
answers
·
Students are guided to answer
the question and contribute
their opinions and the others listen respectly the answer posed.
·
Teacher
asks each students to observe some colloids, and then classify the colloids
types based on its dispersed phase and
dispersing medium.
·
Students
are guided to analyze and interpret their data
Explanation
Phase:
·
Teacher ask each
students to explain scientifically their observation data and their
conclusion
·
Teacher
gives chance to other students to ask some questions and respons about their
friends explanation.
·
Teachers
give the response for the students’ answers, and
re-explain or correct the answers
·
Provide
positive feedback and reinforcement in the form of oral, written, gesture, or
gift for all
group’s answer
Elaboration
Phase:
·
Teacher
asks students to applicate colloid in another terms such as cosmetics, foods,
and pharmaceuticals.
Evaluation
Phase:
·
Students are asked
to answers evaluation sheet
to know how far they learn the concepts of colloid
·
Teacher
guide students to do self evaluation
·
Students
are guided by the teacher to make the conclusion.
|
20 minutes
5 minutes
5 minutes
5 minutes
|
|
3.
|
The final activity (Closing):
·
Teacher
gives students structure task to answer the questions in Bayumedia
Chemistry volume 2B page 160 exercises no 1-10 as homework and ask the student if they can
collect it before next meeting.
·
Teacher gives
students unstructured task reading course
about preparation of colloids from Bayumedia Chemistry Book volume 2B page 130- 147 for next meeting
|
3 minutes
|
VII.
Learning Tools
·
Whiteboard
·
Stationery
·
Power point
contains about colloid and the procedure of colloid
·
LCD
·
Milk, Parfume
Sprayer, Ink, Hair Oil, Cheese, Nail
Polish, Lipstick, Detergent, Water
VIII.
Learning
Resources
1.
Effendy. 2011. A-Level Chemistry for Senior High School
Students Volume 2B. Malang : Bayumedia publishing
2.
Purba, M. 2008. Chemistry Textbooks for Class XII Odd
Semester. Jakarta : Erlangga
Guidelines Scoring
|
No
|
Answer
|
Score
|
|||||||||||||||||||||||||||||||||||
|
1.
2.
|
)
Industrial food: butter, milk, gelatin, spices lettuce, cheese, bread
-)
Cosmetics: perfumes, deodorant spray, liquid to mask, nail polish, facial
cleansing milk and skin, deodorant stick, hair oil (jelly), shaving soap,
beauty soap, lipstick, eyebrow pencil, mascara
-)
Pharmacy: syrup, medicine, capsule
|
3
2
3
3
2
3
3
3
3
|
Evaluation Sheet
1.
Complete the
table below
|
No
|
dispersed phase
|
dispersing medium
|
Colloid types
|
Example
|
|
1
|
|
|
Sol
|
|
|
2
|
Gas
|
Liquid
|
|
|
|
3
|
|
|
Smoke
|
|
|
4
|
|
|
|
Alloys
|
|
5
|
Liquid
|
Gas
|
|
|
|
6
|
|
|
Emulsion
|
|
2.
Describes 3
examples of colloid in terms of cosmetic industry, foods industry and
pharmaceutical!
Key of Evaluation
Sheet
1.
|
No
|
dispersed phase
|
dispersing medium
|
Colloid types
|
Example
|
|
1
|
Solid
|
Liquid
|
Sol
|
mud
|
|
2
|
Gas
|
Liquid
|
Foam
|
Whipped Cream
|
|
3
|
Solid
|
Gas
|
Smoke
|
Dust
|
|
4
|
Solid
|
Solid
|
Solid Sol
|
Alloys
|
|
5
|
Liquid
|
Gas
|
Liquid Aerosol
|
Fog
|
|
6
|
Liquid
|
Liquid
|
Emulsion
|
Milk
|
2. -) Industrial food: butter,
milk, gelatin, spices lettuce, cheese, bread
-) Cosmetics: perfumes, deodorant
spray, liquid to mask, nail polish, facial cleansing milk and skin, deodorant stick, hair oil (jelly),
shaving soap, beauty soap, lipstick, eyebrow pencil,
mascara
-) Pharmacy: syrup, medicine,
capsule
Tidak ada komentar:
Posting Komentar