1.2: The Process of Science
Student Behavioral Objectives
The student will:
- describe the steps involved in the scientific method.
- appreciate the value of the scientific method.
- recognize that in some cases, not all the steps in the scientific method occur, or they do not occur in any specific order.
- explain the necessity for experimental controls.
- recognize the components in an experiment that represent experimental controls.
Timing, Standards, Activities
Lesson | Number of 60 min periods | CA Standards |
---|---|---|
The Process of Science | 3.0 | 1c, 1d, 1f, 1g, 1j, 1k, 1n |
Activities for Lesson 2
Laboratory Activities
- 1. Candle Observation
- 2. Dazoo
Demonstrations
- 1. The Seven-of-diamonds psychic game
- 2. “This” or “That” psychic Game
Worksheets
- 1. Scientific Method Worksheet
Extra Readings
- 1. Science Bakground Information
- 2. Rene Blondolot and N-Rays
- 3. James Randi vs the Dowsers
- 4. The “Mysterious” Bermuda Triangle
- 5. Historical Comparisons
Answers for The Process of Science (L2) Review Questions
- Sample answers to these questions are available upon request. Please send an email to teachers-requests@ck12.org to request sample answers.
Multimedia Resources for Chapter 1
The following web site contains an article titled ‘How the Scientific Method Works’ and also other articles such as ‘History of the Scientific Method’ and more.
The learner.org website allows users to view the Annenberg series of chemistry videos. You are required to register before you can watch the videos, but there is no charge to register. The video called “The World of Chemistry” relates chemistry to other sciences and daily life.
These five 10 minute videos from BBC chronicle a failed search for cold fusion.
The learner.org website allows users to view the Annenberg series of chemistry videos. You are required to register before you can watch the videos, but there is no charge to register. The website has two videos that apply to this lesson. One video called “Thinking Like Scientists” relates to the scientific method. The other video is called “Modeling the Unseen.”
This website has lessons, worksheets, and quizzes on various high school chemistry topics. Lesson 1-2 is on the scientific method.
This video is a ChemStudy film called “High Temperature Research”. The film is somewhat dated but the information is accurate.
Laboratory Activities for Chapter 1
Teacher's Resource Page for Candle Observation
Safety Issues:
If students are allowed to light their own candles, they should be instructed to strike matches on the striker pad in a direction away from the body so that any flying pieces of burning match head move away from the body. Extinguished matches should be held until cool, and then placed in solid waste containers (wastebasket). Students should be reminded that during any lab involving an open flame (candles, Bunsen burners, etc.) long hair must be restrained behind the head so that it does not fall past the face when looking down. Students should be instructed not to handle candles once they are lit. Dripping hot wax can be painful.
Observation List
The candle is cylindrical in shape\begin{align*}^1\end{align*} and has a diameter\begin{align*}^2\end{align*} of about \begin{align*}2 \ cm\end{align*}. The length\begin{align*}^3\end{align*} of the candle was initially about \begin{align*}18 \ cm\end{align*} and changed slowly during observation\begin{align*}^4\end{align*}, decreasing about \begin{align*}4 \ mm\end{align*} in \begin{align*}20 \ minutes\end{align*}.
The candle is made of a translucent,\begin{align*}^5\end{align*} white\begin{align*}^6\end{align*} solid\begin{align*}^7\end{align*} which has a slight odor\begin{align*}^8\end{align*} and no taste.\begin{align*}^9\end{align*} It is soft enough to be scratched with a fingernail.\begin{align*}^{10}\end{align*} There is a wick which extends from the top to bottom of the candle along its central axis\begin{align*}^{11}\end{align*} and protrudes\begin{align*}^{12}\end{align*} about \begin{align*}10 \ mm\end{align*} above the top of the candle. The wick is made of three strands\begin{align*}^{13}\end{align*} of string braided\begin{align*}^{14}\end{align*} together.
The candle is lit by holding a source of flame close to the wick for a few seconds.\begin{align*}^{15}\end{align*} Thereafter, the source of the flame can be removed and the flame sustains itself\begin{align*}^{16}\end{align*} at the wick.
The burning candle makes no sound.\begin{align*}^{17}\end{align*} While burning, the body of the candle remains cool to the touch\begin{align*}^{18}\end{align*} except near the top.\begin{align*}^{19}\end{align*} Within about \begin{align*}5 \ mm\end{align*} from the top of the candle, it is warm\begin{align*}^{20}\end{align*} but not hot, and sufficiently soft to mold\begin{align*}^{21}\end{align*} easily.
The flame flickers\begin{align*}^{22}\end{align*} in response to air currents and tends to become smoky\begin{align*}^{23}\end{align*} while flickering. In the absence of air currents, the flame is in the form shown in the picture\begin{align*}^{24}\end{align*} although it retains some movement\begin{align*}^{25}\end{align*} at all times.
The flame begins\begin{align*}^{26}\end{align*} about \begin{align*}4 \ mm\end{align*} above the top of the candle, and at its base, the flame has a blue tint.\begin{align*}^{27}\end{align*} Immediately around the wick in a region about \begin{align*}5 \ mm\end{align*} wide\begin{align*}^{28}\end{align*} and extending about \begin{align*}8 \ mm\end{align*} above\begin{align*}^{29}\end{align*} the top of the wick, the flame is dark.\begin{align*}^{30}\end{align*} This dark region is roughly conical\begin{align*}^{31}\end{align*} in shape.
Around this dark zone and extending about \begin{align*}5 \ mm\end{align*} above the dark zone is a region which emits yellow light,\begin{align*}^{32}\end{align*} bright\begin{align*}^{33}\end{align*} but not blinding. The flame has rather sharply defined sides\begin{align*}^{34}\end{align*} but a ragged\begin{align*}^{35}\end{align*} top.
The wick is white\begin{align*}^{36}\end{align*} where it emerges from the candle, but from the base of the flame to the end of wick, it is black,\begin{align*}^{37}\end{align*} appearing burnt except for the last \begin{align*}2 \ mm\end{align*} where it glows red.\begin{align*}^{38}\end{align*} The wick curls\begin{align*}^{39}\end{align*} over about \begin{align*}4 \ mm\end{align*} from its end. As the candle becomes shorter, the wick shortens\begin{align*}^{40}\end{align*} too, so as to extend roughly a constant distance above the top of the candle.
Heat is emitted\begin{align*}^{41}\end{align*} by the flame, enough so that it becomes uncomfortable in a few seconds to hold ones' fingers near the flame.
The top of a quietly burning candle becomes wet\begin{align*}^{42}\end{align*} with a colorless\begin{align*}^{43}\end{align*} liquid and becomes bowl-shaped.\begin{align*}^{44}\end{align*} Sometimes, the liquid in the bowl drains\begin{align*}^{45}\end{align*} down the side of the candle, cools, gradually solidifying\begin{align*}^{46}\end{align*} and attaching itself to the candle.\begin{align*}^{47}\end{align*}
Under quiet conditions, a stable\begin{align*}^{48}\end{align*} pool of clear liquid remains in the bowl-shaped top of the candle. The liquid rises\begin{align*}^{49}\end{align*} slightly around the wick, wetting\begin{align*}^{50}\end{align*} the base of the wick as high as the base\begin{align*}^{51}\end{align*} of the flame.
Candle Observation
Materials:
Each student or pair of students is given a candle to observe. The candles should be between \begin{align*}\frac{1}{2}\end{align*} and \begin{align*}\frac{2}{3}\end{align*} inch in diameter (so their length will significantly shorten during the period) and mounted securely in a candle holder (a jar lid will work fine). The teacher should light the candles, give appropriate instructions about hair (it burns), and other safety issues. The student should be instructed to make as many observations about the burning candle as they can in the allotted time. The teacher should encourage estimated quantitative observations.
After the observation period, the teacher can ask for observations from the class and get as many as possible on the board. Further observations can be added from the list above. It is useful for students to recognize that there are many more observations about a simple system than they may have imagined.
Teacher's Resource Page for DAZOO
Question Number | Answer | Reason |
---|---|---|
1. | ZAM | It is a family and they are outside the cages. |
2. | NOOT | It is a single male outside the cages. |
3. | NIX | It is the largest number of individuals in a cage. |
4. | GOBBIE | They have eight legs. |
5. | BOBO | There is no large circle in the cage. |
6. | YATZ | There is no large rectangle in the cage. |
7. | BOBO | There are two small circles in the cage. |
8. | YATZ | There are three small rectangles in the cage. |
9. | CLINT | There are no small circles or rectangles in the cage. |
10. | ARDZU | Circle in circle - mother is pregnant - can't be SLIP because the child is inside of a male. |
11. | Girl | The baby is a circle - which represents female. |
12. | SLIP | There is a small BOBO rectangle inside the large SLIP rectangle. |
13. | BOBO | The crocodile ate a small giraffe. |
14. | YATZ | They have wings. |
15. | WHEE | They have no legs. |
16. | NIX | They live between YATZ and CLINT. |
Observation Game: DAZOO
SET-UP: Teacher prints out a copy of the game image and a set of questions for each student. With a little thought, most students can answer the questions without teacher input.
Only one family and the zookeeper are at the zoo today. The zookeeper is a single male, but the family visiting the zoo has both males and females in the family. The family groupings of the zoo families have been given surnames and are identified by the surnames in the diagram. Try to answer the questions below.
- What is the name of the family visiting the zoo?
- What is the name of the zookeeper?
- Which family in the zoo has the most members?
- What is the name of the family of spiders?
- Which mother is away at the hospital?
- Which family has no father?
- Which family has two daughters?
- Which family has three sons?
- Mr. and Mrs. Elephant have no children. Which family are they?
- What will be the last name of the baby tiger when it is born?
- Will the baby tiger be a boy or a girl?
- Mr. Crocodile has swallowed the giraffes son. Which is the family of crocodiles?
- Which is the family of giraffes?
- Which is the family of pelicans?
- Which is the family of snakes?
- The aardvarks live between the pelicans and elephants. Which is the family of aardvarks?
Demonstrations for Chapter 1
The Seven-of-Diamonds Game
This is the easiest of the observation and hypothesis games. To play the game, the teacher must select and instruct an assistant to play the role of “psychic.” The teacher draws the seven-of-diamonds set up on the board as shown below.
To begin the game, the “psychic” is sent out of the room. While the psychic is out of the room, the students select one of the cards and inform the teacher which card. Then the psychic is called back into the room and the teacher points to one of the cards and asks the psychic, “Is this the card?” The psychic responds either “yes” or “no” and the process continues until the teacher points to the correct card and the psychic correctly identifies the card as the one the students had selected. The students are to observe the game and after each trial run, make hypotheesis about how the trick is being done. They can do this as individuals or in groups. the game can be played over and over until at least one student or group figures out how the trick is being done. When a student or group thiks they know the trick, they can go out of the room with the psychic and then play the role of the psychic when they return. If they can correctly identify the selected card, they win the game. The game can continue until more students figure it out or the winners can explain the trick to those who didn't figure it out.
THE TRICK
The layout of the cards on the board and the spots on the seven-of-diamonds exactly correspond. The psychic will not know the correct card until the teacher points to the seven-of-diamonds and asks, “Is this the card?” When the teacher points to the seven-of-diamonds, he/she points to the spot on the card that corresponds to the card selected. In the picture above, the teacher is pointing to the spot on the seven-of-diamonds that corresponds to the position of the “6” in the layout. Therefore, the six-of-diamonds is the selected card for this trial. The psychic continues to say “no” until the teacher points to the six-of-diamonds and then says “yes.” You should note, it is not possible to have the psychic identify the correct card on the first try unless the selected card is the seven-of-diamonds. If the seven is the selected card, the teacher can point to the seven first and point to the center position. The psychic must be alert to get this one. The teacher can vary the sequence of asking so that sometimes, the selected card is pointed to on the second try or the fourth try, and so forth.
“This” or “That” Psychic Game
This is the most difficult of these observation/hypothesis games for the students to figure out. The teacher draws 3 columns of 3 squares each on the board as shown at right. Once again, the teacher needs an assistant to act as psychic. Secretly, the teacher and the “psychic” conspire and assign the two outside columns to be called “this” columns and the middle column to be called a “that” column.
As usual, the psychic leaves the room and the students select one of the squares to be “psychically” identified. The psychic is called back into the room and the teacher proceeds to point at various squares and ask the psychic, “Is it this one?”, or “Is it that one?” The code known only to the teacher and the psychic is that if the teacher uses the correct name of the column when inquiring about a square, the psychic answers “no.” If the teacher uses the incorrect name of the column when inquiring, the psychic replies “yes.”
One of the things that make this game so difficult is that the teacher can ask about the correct square on the first try. On the very first trial, the teacher can point to a square in the middle column (the “that” column) and ask, “Is it this one?” and the psychic replies “yes.”