The fourth grade composition of experimental primary school 1 "Ding Yisheng, the class began, and I quickly sat down in my seat and waited for the teacher to come to class. At this moment, the teacher came in. She is wearing a dress and a pair of high heels, and her appearance is gentle. The teacher first put the file bag in his hand on the platform, and then took out a beaker, a toothpick and a bottle of detergent from the treasure chest. Out of curiosity, we leaned out and carefully observed the teacher's every move. I saw the teacher slowly say to everyone, "Students, let's do an experiment today, shall we?" The students said in unison, "Good! "Then, an interesting experiment began.
At first, the teacher went to the water cooler, poured a full glass of water into the beaker, then wiped a little on one end of the toothpick with detergent, and then carefully put the toothpick into the beaker. Each of us stared at the beaker intently. The classroom is very quiet, and we can hear the sound of needles falling. At this time, the toothpick is like a boat, drifting straight forward. We were very surprised and began to ask the teacher why. The teacher said cheerfully to everyone: "Because the detergent will have a strong driving force when it meets water, the' boat' will move forward." We listened, as if we had parted the dark clouds and met the blue sky. I think this experiment is really interesting!
At the end of class, the teacher said to everyone, "There are still many mysteries in our lives that need our careful observation. Let us explore and study these mysteries with wisdom! "
Can shampoo be dissolved in water? Is hot water dissolution the same as cold water dissolution? With these two questions, I started this interesting little scientific experiment at home.
The experimental materials I prepared are: two transparent glasses, measuring cups, chopsticks and shampoo.
After the preparation, I can't wait to start the experiment. I first put two cups flat on the table, then measured 120 ml of cold water and hot water from the cups, poured them into the cups respectively, and then dropped a drop of light green shampoo into each cup. I opened my eyes and carefully observed the change of shampoo in water.
Shampoo drops in cold water, first naughty floating on the water, and then slowly sinking, like a weed. What about those in hot water? Shampoo quickly sank to the bottom of the water in a few seconds, and small bubbles appeared at the bottom of the water, like underwater volcanoes. It was so beautiful! When I gently stir, the shampoo spreads and dissolves in the water.
The shampoo in hot water has been dissolved successfully, but the shampoo in cold water is still sinking. "Why is it so slow?" I was so angry that I said to myself. So, I stirred it with chopsticks, and the shampoo broke into several small pieces. I kept stirring, faster and faster. After fully stirring like a shadowless hand, the shampoo rolled in the water like a cloud, evenly distributed in the water, and finally turned into a light green turbid solution.
Through experiments, I come to the conclusion that shampoo is soluble in water, and it dissolves faster in hot water than in cold water. I solved these two problems, and my heart is as sweet as honey.
What an interesting scientific experiment! As long as we do more experiments, find problems and solve them, life will be full of scientific knowledge!
On August16th, the world's first quantum satellite was launched from Jiuquan Satellite Launch Center. Quantum, an ordinary and extraordinary new term, brings me infinite reverie. So, my father and I watched the British bbc documentary about quantum. A small experiment proves the existence of quantum entanglement. I decided to try it myself.
The material of the test is two identical coins, provided that they are completed on a plane. The first time, I turn a coin, turn the second coin while turning the first coin, and then buckle the first one with my left hand. At this time, I don't know which side of the coin is facing up. When the second coin finally stopped naturally, I opened my left hand and found that the first coin was facing up and the second coin was facing up. I tried 10 times and carefully observed their changes. When two coins hit objects around them, they were forced to stop. On one occasion, two coins were with flowers facing up, one coin with flowers facing up and the other coin with words facing up. Eight times, the coins naturally stopped, with flowers facing up and the other coin with words facing up. I thought: this is no accident. Science is amazing! I am ecstatic, my little experiment has succeeded!
This little experiment only proves the basic principle of quantum: there is a certain connection between entangled quanta, and even if they are far apart, they can affect each other's behavior. Do you think this scientific phenomenon is amazing? Do it yourself!
This is a science class, and we did an interesting experiment-how to make potatoes float.
A few days before the experiment, the teacher asked us to prepare a potato and some salt in advance. What kind of interesting experiment will it be?
This science class opened our doubts. It turned out to be an experiment about the rise and fall of potatoes. The materials needed for the experiment are: a glass container, a potato and a bag of salt. After the teacher explained the experimental process, everyone was eager to try and couldn't help but start the experiment. First, cut the potatoes into small cubes and put them in a glass container filled with water. Then, add a little salt carefully. But potatoes don't give us any face. They were still immersed in water and indifferent, so we went to ask the teacher, who said it was because the density of salt water was not high enough.
So, we almost put half a bag of salt. Look! Potatoes float on the water, but only in the middle of the water. It seems that the density of this water is still not high enough.
We decided to add more salt, but I accidentally shook my hand and poured the whole bag of salt into the glass container, but because of this carelessness, the potatoes completely floated. "The potatoes in our group are floating!" I cried with joy and surprise.
It turns out that potatoes can float in water as long as the density of water is higher than that of potatoes. This is really an interesting experiment.
One day in winter vacation, my father and I did a small experiment called "lava lamp".
It's called "lava lamp" because it will emit bubbles continuously after it is made successfully, just like lava eruption. As the name implies, it is called "lava lamp".
Lava lamp needs water, pigment, edible oil and effervescent tablets. Then, my father and I started to do it. I first pour water and red pigment into the glass in proportion and mix them together. Pour in cooking oil and add effervescent tablets. Dad has been watching this process. After reading it, he said quietly, "honey, your ratio seems to be wrong." Too little oil was poured. " . I waited for it to bubble without saying a word, but it didn't seem to achieve the expected effect. Because there is no foam. Oh, I must do it again. I sighed deeply. Dad saw my sad expression and comforted me and said, "Never mind, let's start over."
"well! Let's do it again. "
This time I learned my lesson, took a bigger cup, then mixed water and pigment to 1/3, and finally adjusted the cooking oil to 2/3, and put an effervescent tablet in it. After a while, the effervescent tablets reacted and emitted "beep" bubbles. Because water is heavier than oil, oil floats on it. From above, it looks as if magma is about to erupt. After a while, I finally succeeded.
This time I learned a truth, that is, don't give up easily, and we are getting closer and closer to success.
In this experiment, I not only learned knowledge, but also did an experiment, so happy!
Composition 6 of the fourth grade of experimental primary school studied the text "Fishing of Iron Bull" and learned that Huai Bing used the buoyancy of water to "send" the iron bull back. But is water really so buoyant? So, with this question, I asked my father to do the experiment with me.
Dad first asked me to go to the dormitory site to get some sand, then he brought a bathtub full of water, made a heavy object to sink into the water as an "iron cow", and prepared two small wooden bowls with half a bowl of sand in them and put it where the heavy object sank. Finally, put a shelf on two small wooden bowls with iron bars and prepare a rope. The iron frame rolled into the water and the experiment failed. I am not discouraged. I observed that iron bars are cylindrical and roll easily. When the wooden bowl shakes, it will roll into the water. So, I replaced the iron bar with longer and thicker bamboo pieces and fixed them on two small wooden bowls. Then I tied one end of the rope to the shelf and the other end to the weight. Finally, I slowly scooped up the sand in the bowl with a spoon. As the sand gradually decreased, the two wooden bowls rose slowly, and the weight tied to one end of the rope floated up bit by bit. Finally, the sand was scooped up and the heavy objects floated to the surface. Seeing the success of the experiment, I danced with joy. The success of the experiment made me feel happy, increased my knowledge and gave me a deeper understanding of the text.
I saw an interesting little experiment on the computer today.
After watching the experiment, I immediately jumped up and looked for materials, namely: eggs, salt, water and washbasin. I fill the washbasin with water first, and then put the eggs in it. I try my best to make eggs dance on the water. But the result is the same. The egg has been lying underwater and refused to move.
After a while, we thought of an experiment. If you put a little salt in the water, the eggs will float. I put a spoonful of salt into the water with a spoon. Eggs make a little noise, just like a baby stretching in the middle. I felt as if I had to put salt again, so I put a little more, and soon the eggs danced a fancy ballet on the water.
Do you want to know why? Because the weight of an egg is heavier than the same volume of clear water, it will sink in clear water. But compared with the same body of salt water, the weight of eggs is lighter, so eggs will float on salt water.
We can do more experiments in the future, which not only enhances our hands-on ability, but also increases our knowledge.
The fourth grade composition of experimental primary school 8 small experiments in life Zheng, Class Two, Grade Four, Shaxian Experimental Primary School, Sanming City, Fujian Province. You must know water, detergent and cooking oil. Today, my experiment is about their three liquids.
Please pay attention. The experiment has already started.
In the first experiment, I took out a transparent cup, added water to the cup, and then dropped cooking oil into the water. Gee! How can oil float on the water and not sink? Is water heavier than cooking oil? I turned on the computer with a question, searched it over and over again, and finally found it, alas! The result is that the specific gravity of water is heavier than that of cooking oil!
The first experiment is over. Let's look at the second experiment. I took out a transparent cup, added as much water as the first one, and then dropped the detergent into the water. I guess it must be floating like oil! I didn't expect the detergent not to float up, but to sink into the water and disappear into the water. It's fake. Yes, it's fake. I want to tell my mother. I thought to myself. Thinking of me, I ran to tell my mother.
"Silly boy, this is not fake. This is because water dissolves the detergent. " Mom smiled and said:
The third experiment began. In this experiment, the same amount of liquid in the first two cups is poured into a new transparent cup, and the water becomes clear. I was confused, so I turned on the computer and looked it up. It turns out that detergent can decompose oily components and make them compatible with water.
Students, as long as you carefully observe the little things around you, you will gain a lot of knowledge.
Composition 9 of the fourth grade in experimental primary school I talked about science experiments last Wednesday. In fact, my teacher told me last Monday, and I was very excited when the teacher said it! When I got home, I quickly finished my homework and began to play the piano. At dinner, I told my parents about this happy event. I'm so happy!
After dinner, according to the teacher's request, I started to do PPT.
First of all, this is my first time to do PPT. I can't do it. I looked at it and let me click enter. I clicked on it, started typing, and lost. I want to make the next page, but I can't go to the next page by clicking. At this moment, my "savior" father came and showed it to me. I did the same thing, first clicked the right button ... PPT was finally finished.
What I want to talk about is the experiment of lifting bottles with nuts. Nuts, pipes, bottles and ropes are all things that need to be prepared. When you are ready, wait until Wednesday.
Wednesday finally arrived. In the afternoon, I was very nervous, waiting for the bell for class. The bell is ringing! I started playing PPT.
I said, "Today, I will use a nut to lift a bottle." I took a deep breath and began to talk about "preparing tools …". I began to do experiments. I picked up the test tube and began to spin. The bottle has really gone up! I asked everyone to do it, and they all succeeded. Time passed quickly, and before I knew it, the class was over, and I felt very successful, as if I had won the battle.
When I got home, I thought it was very difficult to do a good job, and only by persistence can I succeed.
This morning, in the second Chinese class, the Chinese teacher came to the podium with a raw egg, a chopstick, a glass of water and a bag of salt. When the students saw it, they began to chirp. Some students said, "Is it difficult for the teacher to make drinks for us?" Some said, "What does the teacher want?" Suddenly, at the teacher's command, the classroom that was just chattering suddenly became silent. At this time, the teacher said mysteriously, "Let's do an experiment to make eggs surface." I thought: how can an egg float? What medicine is sold in the teacher's gourd?
The experiment began, and the teacher put the eggs in clear water. Eggs sink to the bottom of the water, just like a sleeping doll and a golden dough lying on the bottom of the water. The Chinese teacher put a little salt in the cup and stirred it with chopsticks, but after a while the egg sank, huh? What's going on here? Is there too little salt? Then, the teacher put a lot of salt in the cup. The teacher stirred hard with chopsticks, the water gradually turned milky white, and the eggs slowly floated up, just like a submarine slowly floated up. The students were surprised to see it and talked about it one after another. Some said: How can eggs float? Some are burying their heads in thinking at their desks. The teacher told us that the proportion of water is smaller than that of eggs, so the eggs will sink to the bottom. If you add salt to the water, you can increase the proportion of water, so that the eggs will float slowly.
I'm really surprised and happy. The world is really wonderful.
Composition for the fourth grade of experimental primary school 1 1 "Success, success." The classroom is noisy. What happened in the end?
The thing is this: Miss Wang gave me an experiment. This lab is like this: Teacher Wang takes out salt, spoon and pepper. The students in the classroom saw it and immediately raised their hands and asked, "What are you doing, Miss Wang?" Teacher Wang didn't speak, just took out a blank sheet of paper. Teacher Wang said, "Let's do an experiment of salt and pepper first, and then separate them." Later, a classmate said, "You can pour pepper and salt into the water." After the classmate finished speaking, Mr. Wang took out his cup and poured salt and pepper into the water. Suddenly, pepper is at the top and salt is at the bottom. After that, tell the truth; "Although this is a good idea, but the spoon and white paper have no effect? Who else has a way? " No one raised his hand, so Mr. Wang had to do it himself. She poured pepper and salt on the white paper, then stirred it, took out a spoon and rubbed it on her arm for a while, then rubbed it on the powder a few times, and the pepper was sucked up. Last night, Teacher Wang said, "This is the scientific principle of friction."
This is really an interesting experiment!
Today, the teacher brought us an egg, a glass of water and a bag of salt to cook for my mother. Looking at the tools the teacher put on the lecture table, none of our classmates knew what medicine the teacher was selling in the gourd. The teacher told us that we were going to see eggs and learn to swim today. We are all confused. How can an egg learn to swim without long arms and legs? So, the teacher decided to do the experiment for us personally.
As soon as the teacher put the egg into the water glass, he saw that the egg staggered down like a drunk, and soon sank to the bottom of the cup and "slept" motionless. Then the teacher stirred it with chopsticks. Unexpectedly, the egg shook its lazy body and fell down again. At this time, the teacher added a few spoonfuls of salt to the cup and continued to stir with chopsticks. The egg wobbled and slowly straightened up, and the Buddha suddenly became lighter and stood up from the bottom of the cup. Like a doll who just woke up from sleep, she floated upward. After a while, the egg floated to the surface like a diver's oxygen bottle, and there was no oxygen to breathe.
Do you know why eggs float? The teacher revealed the experimental principle to us: It turns out that when salt is added to clean water, the density of water increases and the buoyancy increases, and the eggs will float. Just like why people can float on the dead sea at will, the reason is the same.
The little egg is a big mystery, so we must pay more attention to it in our life and learn everywhere in order to make more discoveries.
The fourth grade composition of experimental primary school 13 I remember walking on campus one day and found many paintings hanging in the cultural corridor, each with a magic cup. Why do I say that the ordinary cup in the picture is a magic cup? Oh, it turns out that the water in the cup is not only one color, but colorful. It seems that this cup can put the rainbow far away into your stomach, so that everyone who sees it feels that the rainbow is close at hand. In this winter vacation, I can finally make this magical little cup-rainbow cup!
I invite my good friend to do this experiment with me every day. We found honey, detergent, transparent cups, water and red wine at home, but we couldn't find watercolors! Finally, I had to give away the Chinese painting pigments that I used only once that year. Everything is ready, and the experiment confirms. We first slowly put honey into the cup. But miss honey, who likes to be picky, just doesn't want to settle down in a cup. Because honey is too sticky, she climbed into the cup like a snail. Then, we slowly put our dear sister in red into the cup. However, in desperation, Sister Shui wore a blue skirt and rushed into the cup before I could reach her. Finally, red wine and oil are poured into the cup in turn.
Finally, I made a magical and beautiful four-color rainbow in the cup with some common materials! Looking at the rainbow cup I made, I was full of excitement and curiosity …
The fourth grade composition of experimental primary school 14 walked in from the school gate, and a huge stone stood on the lawn, engraved with a big word "truth", which echoed the school motto of "sincerity-oriented, seeking knowledge and seeking truth" hanging outside the teaching building.
On the right side of the boulder is a five-story teaching building with red tile walls and rows of transparent windows. The classroom is clean and bright, and the desks are neat.
Boarding the bird's-eye view of the teaching building, most of the campus scenery is under your eyes.
Right in front is the front square of the school, with green grass and red flowers. Under the sunshine, the grass is greener and the flowers are brighter. Bright five-star red flags fluttered in front of the square.
The display window downstairs is full of students' works, including exquisite calligraphy, exquisite paintings and exquisite models.
Look west, the playground is downstairs. There is a basketball court in the middle of the red runway. At this end of the runway, it is the single parallel bars, and at the other end, it is the sports building. On holidays, students perform in the gymnasium. On rainy days, students are very active in the gym.
After visiting Ningbo Experimental Primary School, I love her even more.
I used to like carbonated drinks. Father disagreed and said, "carbonated drinks are bad for our health, which will make the calcium carbonate in our bones rot."
I don't believe it. My father asked me to put an egg in a cup of vinegar and observe its changes. I did it. The eggshell is so hard that it hasn't changed at all. After a while, many small bubbles appeared on the eggshell, which gradually became bigger and finally floated. I fished out the eggshell with a small spoon and found that it was full of small bubbles, some of which were embedded in the depths of the eggshell like gems. After a while, I found some white places on the shell, and I suspected that it had lost its shell. After a while, I scraped it with my nails and found that one layer of the shell was scraped off and the shell was corrupt. A day later, the eggshell became transparent.
Dad explained to me, "Our bones and eggshells contain a lot of calcium carbonate. Carbonated drinks, like vinegar, will' eat' the calcium carbonate in the bones and make the bones loose. " Finally, I think carbonated drinks are really not drinkable!