4th Grade Book Table of Contents
Dissolution/Sound/Weather/Our Body
Dissolution
1, Water can dissolve some substances
2, How does water dissolve substances
3, The phenomenon of dissolution between liquids
4, the ability of different substances to dissolve in water
5, the speed and slowness of dissolution
6, how much table salt can be dissolved in a cup of water
7, methods of separating salt and water
Sound
1, listen to the sound
2, how the sound is produced
3, changes in the sound
4. Exploring the pitch change of a ruler
5. How sound travels
6. How we hear sound
7. Protecting our hearing
Weather
1. We care about the weather
2. Weather Calendar
3. Temperature and Air Temperatures
4. Wind Direction and Wind Speed<
5, Measurement of Precipitation
6, Observation of Clouds
7, Summarizing Our Weather Observations
Our Bodies
1, Structure of the Body
2, Bones, Joints, and Muscles
3, What Happens When You Jump (I)
4, What Happens When You Jump (II)
5, Food travels in the body
6, Changes in the mouth
7, Taking care of our bodies
Lesson 1 Water dissolves some substances
Teaching Objectives
Science Concepts:
Some substances dissolve readily in water, and some do not dissolve readily in water.
It is not easy to separate dissolved substances from water by filtration.
Processes and methods:
Observe and describe how salt, sand, and flour do and do not dissolve easily in water,
Able to use filtration devices to separate several solids from water mixtures.
Emotions, attitudes and values:
Experiencing the fun of studying the phenomena of dissolving and not dissolving easily, and stimulating the interest of further investigating the problem of dissolving. In the observation and comparison activities, be able to realize that careful observation will make the description more accurate. Strictly in accordance with the norms to carry out experiments using the dissolving device.
The teaching focuses on describing the main features of the phenomenon of dissolution of salt, flour and other substances.
Teaching Difficulties Compare the similarities and differences in the changes of table salt, sand and flour in water.
Teaching Preparation
Grouping materials: table salt 1, sand 1, flour 1, water-filled beaker 3, chopsticks 1, glass rod 1, sink 1, funnel 1, filter paper 3, iron stand 1. (Sand is panned before use.)
Teaching process
I. Salt dissolves in water
1. Students observe the experiment: take a small spoon of salt and a small spoon of sand, respectively, into two water-filled glass cups, do not stir, observe quietly, and compare the changes of salt and sand in water. After a while, stir again and observe their changes.
2. Students report their observations: how does the salt change in the water? Sand in the water? (Note to correct the students report: salt in water is easy to dissolve, sand in water is not easy)
3. Organize a discussion: what phenomena allow us to determine that "salt in water is easy to dissolve"? What phenomena can we judge "sand in water is not easy to dissolve"? (The phenomenon of dissolution of salt and the phenomenon of sand does not dissolve easily.)
Second, flour dissolved in water
1. Teachers explain: salt in water is easy to dissolve, the formation of a solution we can call salt solution; sand in water is not easy to dissolve, we call it a mixture of sand and water. What happens to flour in water?
2. Student experiment: take a small spoon of flour, put a glass of water, quietly observe for a while, to see the change of flour in the water, and then gently stir with chopsticks for a while, to observe the change of flour in the water.
3. Organize and report: Does flour dissolve easily in water? What other phenomena can we observe when we leave it for a while?
4. Teachers guide the description: what is the state of flour in water?
5. Discuss: What are the similarities and differences in the dissolution of flour, sand and salt in water? Did the flour dissolve in the water?
6. Teacher guidance: in order to make further observations, we can use the method of filtration. Demonstration of paper folding and filtration experiments, be careful not to splash the liquid outside the filter paper, pour the liquid into the funnel to be slightly below the top edge of the filter paper.
7. Student experiments: respectively, do filter salt solution and sand and water mixture and flour and water mixture, and observe the filter paper, report observations.
8. Exchange the results of the experiment, organize the new understanding of dissolution recorded in the science notebook. (Remind students that dissolving is not melting or fusing.)
Board Design:
After Teaching:
Lesson 2 How Water Dissolves Matter
Teaching Objectives
Scientific Concepts:
Dissolution is the dispersion of a substance uniformly and steadily in water, and it cannot be separated out by filtration or by settling.
Process and Methods:
Observe and describe the process of dissolving potassium permanganate in water and imagine the process of dissolving table salt.
Emotions, attitudes and values:
Recognize the importance of careful observation in experiments.
Teaching focuses on describing the main features of the phenomenon of dissolution of substances such as table salt and flour.
Teaching Difficulties Compare what are the similarities and differences in the changes of table salt, sand and flour in water.
Teaching Preparation
Grouping materials: water-filled beaker 4, chopsticks 1, potassium permanganate 1, a small medicine spoon, salt 1, sand 1, flour 1.
Teaching process
I. Observation of potassium permanganate dissolution
1.Guided by the imagination: the process of dissolution of salt in water.
2. Teacher explains: in order to clearly observe the process of dissolution, we use a colored substance to do dissolution experiments. Teachers show potassium permanganate. (Teachers take and put the demonstration to be standardized, this is the students' first contact with chemicals)
3. Guided observation to describe: potassium permanganate is a kind of substance?
4. Student experiment: in a beaker filled with water, gently put a few small particles of potassium permanganate, first static observation of potassium permanganate in the water dispersion phenomenon, and then use chopsticks to gently stir the water, and continue to observe the changes in the water and potassium permanganate. (Pay attention to students' description of the details of the observation)
6. Students report: What kind of changes did the potassium permanganate have before and after it entered the water? Did it dissolve in the water? What are the similarities and differences between its dissolution in water and that of table salt?
Second, the dissolution of different substances in water
1. Observation and recording experiments: further observation of salt, sand, flour and potassium permanganate dissolved in water, compare what they are the same and different in water. (Observations can be recorded directly in the table in the book)
Size of the particles that become
Distribution in the water
Whether they precipitate
Can they be separated by filtration
Whether they are dissolved or not
2. Group communication: correct the descriptions and records.
3. Class discussion and exchange: can we observe and distinguish whether a substance has dissolved in water? How do we observe and distinguish?
4. Organize and record: students' knowledge of the characteristics of dissolution is recorded in their science notebooks.
Board Design:
After Teaching:
Third Lesson: Dissolving Phenomena Between Liquids
Teaching Objectives
Scientific Concepts:
Scientific concepts: Initial perception and understanding that dissolving phenomena can take place between a variety of states of matter (liquids and solids, liquids and liquids, liquids and gases);
Processes and Methods:
Processes and Methods:
To further observe dissolution between a variety of substances with the aid of experiments. further observe the dissolution phenomenon between many kinds of substances, and distinguish some common dissolution phenomena according to the main characteristics of dissolution.
Emotional attitudes and values: in the observation, communication, will see the new "dissolution" phenomenon and the known comparison, in the process of generating the desire to explore more dissolution phenomena.
Teaching focus on the main features of dissolution to distinguish between other more easily dissolved and not easily dissolved phenomena
Teaching difficulties in the observation and perception of air dissolved in water
Teaching Preparation
Teaching preparation
Group observation experiments with: glasses, droppers, alcohol, edible oils, and some other non-aqueous liquids; Sprite (soda), syringes, test tubes, test tube clips, Alcohol lamps, matches, etc.
Teaching process
1. Introduction
-The teacher prepares a cup of water and a bag of coffee. Students observe the phenomenon after the coffee is stirred in the water.
-What happened to the coffee in the water? What did you observe that indicated that the coffee dissolved in the water?
-We already know that solids such as salt, sugar, soap, and coffee can be dissolved in water. So can other liquids and gases dissolve in water?
2. Observe dissolution and insolubility between liquids
- Put a few drops of alcohol in water and observe whether the alcohol dissolves in water?
- Put a few drops of water in alcohol and observe if the water dissolves in the alcohol?
- Put a few drops of cooking oil in water and observe if the oil dissolves in the water?
- Put a few drops of water in cooking oil and observe if the water dissolves in the oil?
-Question: do alcohol and water dissolve in each other? Do cooking oil and water dissolve in each other?
-Use the same method to observe more liquid-to-liquid dissolution.
-Question: which liquids dissolve each other and which do not dissolve each other easily?
3. Observing Gases Dissolved in Liquids
(1) Observing Carbon Dioxide Dissolved in Sprite (Soda)
-Open the cap of the Sprite (soda) bottle and observe the bubbles escaping from the liquid. This is the gas dissolved in the drink.
- Suck up one-third of the liquid with a syringe, then seal the mouth of the tube with a rubber cap, then slowly pull outward (push inward) the piston of the syringe, and observe the change of gas and liquid in the syringe.
-How do you explain the changes in the gas and liquid in the syringe?
(2) Observe air dissolved in water
- Is there air in this glass of water? What do you think? (Extraction of life experience)
- Fill a test tube 1/3 full of water and heat it slightly on an alcohol lamp. Observe if small bubbles appear on the walls of the test tube.
-How can this phenomenon be explained?
4. After the lesson, continue to observe what other objects can also dissolve each other.
After the lesson:
Lesson 4: Solubility of Different Substances in Water
Teaching Objectives
Science Concepts:
Science Concepts: Different substances have different solubility in water. Some gases also dissolve easily in water.
Process and method: to study the solubility of table salt and baking soda in water. Conduct experiments on the dissolution of gases in water.
Emotions, Attitudes and Values: Recognize the importance of careful observation and comparison in dissolution experiments. Realize the wide application and importance of dissolution in life.
Teaching focus on understanding the different solubility of different substances in water.
Teaching DifficultiesStudy the dissolution of gases in water.
Teaching Preparation
Group experiments: beaker with 30 ml of water 2, chopsticks 1, small spoons 2, 20 grams of salt, 20 grams of soda, soda 1, corkscrew 1, syringe 1.
Teaching Procedure
I. Study the solubility of salt and baking soda in water.
1. Students observe: open the paper packet on the table and say do you know what is inside?
2. Teacher question: to 20 grams of salt and 20 grams of baking soda at the same time in the same amount of water to do dissolution experiments, guess, salt and baking soda who is in the water dissolution ability?
3. Guide the experimental design: how to carry out this comparison experiment is more fair?
4. Organize students' experiments: remind students to keep good records of their experiments.
5. Reporting:
2. Observation of the solubility of gases in water
1. Teachers show a bottle of soda, shake it and ask the students to observe the bubbles appearing in the liquid.
2. Teacher explains: the bubbles that escape from the liquid when we shake the bottle are the gases dissolved in the drink. Do you know what kind of gas it is?
3. Student experiment: observation of carbon dioxide dissolved in soda
4. Introduction of the procedure: use a syringe to suck one-third of the liquid, and then seal the mouth of the tube with a rubber cap, and then slowly pull outward (push inward) the piston of the syringe, and observe the change of the gas and liquid in the syringe.
5. Question: how to explain the changes in the gas and liquid in the syringe?
6. Organize your record of understanding from this lesson into a science notebook. (Refer to P10)
Expand: How do you observe air dissolved in water?
Board Design:
After Teaching:
Fifth Dissolving Fast and Slow
Teaching Objectives
Scientific Concepts:
The speed with which soluble solids can be dissolved in water is related to the size of the particles of the object (i.e., the size of the surface area), the temperature of the water, and whether or not the mixture of the solution is stirred.
Process and Methods:
Guides students through the " Question - Hypothesis - Verification - Confirmation" process of scientific inquiry and the process of controlling a single variable for a comparative experiment.
Emotional attitudes and values:
Willing to apply the scientific method of comparative experiments to the study of solving the same kind of scientific problems, and develop a sense of fair experimentation. Experience the fun of studying the factors affecting the speed of dissolution.
Teaching focus on the dissolution of sugar cube experiment
Teaching difficulties in the process of comparative experiments, a variety of the same conditions of control
Teaching preparation for group experiments: chopsticks 1, glass 2, hot water and cold water, sugar cubes 3, salt 1, spoons 1, sink 1.
Teaching process
I. Which one dissolves faster.
1.Review: what are the characteristics of an object dissolved in water?
2. Question: Take two equal portions of table salt, about 10 grams each, and put them into the same amount of water (25 ml) at the same time, and observe and compare which one cup of table salt dissolves a little faster.
3. Students observe the experiment. (Teachers guide the comparison method)
4. Organize the observation information and exchange ideas.
5. Present new conditions: does temperature have any effect on dissolution? (Around 60 degrees Celsius, emphasizing safety.)
6. Students observe the experiment. (Teachers further guide the experimental operation)
7. Organize the observation information for exchange.
Two, to speed up the dissolution of sugar cubes
1. show the sugar cubes: a piece of sugar in the water to dissolve faster or slower by what factors?
2. Students conjecture to form a hypothesis: with stirring can make the soap dissolve faster; hot water is easier to dissolve soap than cold water; cut the soap into small pieces easier to dissolve; add more water to make the soap dissolve faster ......
3. Develop an experimental design. (Groups design experiments and document the design using methods such as diagrams or words.)
(1) Group discussion: how to use experiments to test their hypotheses (each group designs one or two experiments to confirm their conjectures).
(2) each group's experimental design exchange report to add and improve. Teacher board the same conditions and different conditions. (Focusing on the guidance of the control of variables in the comparison experiment.)
(3) Ask a group to demonstrate one of the comparison experiment, the rest of the students observe and comment to ensure that each group can operate correctly.
4. Students experiment in groups, report the results, respond to the hypothesis, summarize and evaluate. (Pay attention to guide students to reflect on the shortcomings of the experimental process)