Narrative Composition of Grade Two: An Interesting Experiment 1 I like the book "We Love Science" best, especially the column "Experiment with Hands". There are more than 10 small experiments every time. Every time I start subscribing to an activity, I scramble to pay. Therefore, this magazine has benefited me a lot.
Once when I was reading a book, I saw a title that attracted me. The topic is that eggs can float in salt water. I thought: this is nonsense. How can eggs float on the water? But another thought: this column was written by an expert. How could it go wrong? I first prepared some materials according to the book, poured half a bag of salt into the cup in order, and stirred it quickly with chopsticks to make the salt dissolve quickly, but I had a lot of questions in my heart. Anyway, you can't go wrong as long as you follow the book. I saw a strange light in the cup, colorful and changing like a rainbow. These should be crystals of salt. Is light reflected from these crystals? At this moment, I put down an egg and a miracle happened. The egg didn't sink, but floated on the water. This scene surprised me, and it took me a long time to come to my senses. I thought: What the hell is going on here? I quickly opened the book "We Love Science", which read: Originally, eggs could not float in the water, but with the addition of salt, the buoyancy of the water was greatly increased, and the eggs were lifted. Oh, that's why miracles happen.
I suddenly understood that such a simple experiment implies such a profound truth! I am really happy, because I not only know a knowledge about water buoyancy, but also cultivate my practical ability. This experiment is so interesting.
Narrative Composition of Senior Two: An Interesting Experiment 2 Once, my brother suddenly asked me a question: "Why don't people sink in the dead sea, but float?" Dad said, "That's because the water in the Dead Sea is salty." I am thinking: What is the relationship between the salinity of water and buoyancy?
I was puzzled and decided to do a scientific experiment. I brought a big water cup to hold water, and then I put an egg in it. The egg shook and sank to the bottom. I thought: Is the saltier the water, the greater the buoyancy? To prove this point, I took a bag of refined salt and poured some into the water. The egg shook slightly, but did not move, as if asleep. Is the water not salty enough?
I cruelly put some quicksand salt into the water. I stared at the little lazy egg at the bottom of the water and saw that he seemed frightened and turned over to get up. Ah, victory is in sight! My eyes are almost round and my face is almost glued to the glass. But the disappointing egg just floated, dozed off again and lay motionless at the bottom of the cup.
At this time, the water has turned milky white, and thick refined salt is deposited at the bottom of the cup.
Ah! The salt has not melted yet! No wonder eggs can't float. I took a chopstick and stirred it in the water. Soon, the egg seemed to be wearing a life jacket and staggered out of the water, but when it rose to half, I cried happily. Unexpectedly, I was so happy that I knocked over the cup. Helpless, I can only do it again.
I'd better put the eggs at the bottom first, and then pour in some salt. I put the egg in the cup for one minute, two minutes ... after five minutes, the egg gradually floated to the surface with the melting of salt. Yes, my experiment succeeded!
From this experiment, I understand a principle: the saltier the water, the greater the buoyancy.
Narrative composition of the second day of junior high school: An interesting experiment 3 saw him on the stage with a ferocious face and a "fake newspaper" in his hand. Tell you, we are conducting a large-scale "super experiment"-can a piece of paper be folded nine times? Let's start the experiment!
The teacher gave everyone a rectangular piece of paper. After listening to the teacher's rules, we are already eager to try. "Let's go!" As soon as we spoke, we folded the paper in half, folded it in half, and folded it in half again ... by the sixth time, we began to lock our eyebrows and grind our teeth, which was particularly difficult. But in the end it ended in failure for the eighth time.
Isn't the truth based on Qian Qian's absolute practical actions? So we didn't give up and began to continue the experiment.
This time, the teacher changed a big newspaper and invited a classmate to give a demonstration on stage. I saw a confident expression on his face. He gently folded the newspaper in half with his fingers, as if he would win this time without a doubt.
With the increase of paper thickness, the hardness also increases. The students were not as relaxed as before, their brows began to wrinkle slightly, and their mouths began to hiss, as if thinking: Huh? What's going on here? This is not logical thinking!
Rubbing and beating, finally the seventh time, the classmate said, "Brother, I tried my best!" " "We suddenly" alas! "
At this time, a "green messenger" stepped forward, holding a newspaper and pressing it hard with his muscles. Suddenly, the air in the classroom seems to have solidified, and we are looking forward to …
"Yes! The eighth success! " We cheered. However, the ninth time is hopeless.
Truth is obtained through many experiments, and practice is an indispensable part of obtaining truth!
Narrative Composition of Junior Two: An Interesting Experiment 4 "Ding Lingling ..." is coming to class. Teacher Gong came into the classroom mysteriously with a cup and a hot kettle. The students are whispering to each other. Is teacher Gong going to do the same thing again and become a potato with us? Seeing the teacher smiling without a word, the students were even more surprised. What medicine is sold in the teacher's gourd? I must have a look.
Look, the teacher put the cup on the platform and took out a pack of Chinese wolfberry from his pocket. The students all booed: "Teacher, are you going to treat us to gouqi tea?" The teacher is still the suspense, smiling without a word. Finally, when we saw our vacant faces, we took action.
The teacher first put a dozen Lycium barbarum into the cup, and then poured more than half a cup of boiling water into the cup. Lycium barbarum suddenly floated to the surface of the water, except for one who seemed to be wearing a golden bell and iron cloth shirt, and was not afraid of scalding at all. Those floating medleys seem to be running a marathon, scrambling to run up.
Seeing this, we quarreled again. How did this happen? The teacher unhurriedly fished out the unsinkable "diehard loyalty" in the cup and said, "Let's find some companions for this little wolfberry." After that, I picked up a small wooden stick and pressed the full medlar into a medlar cake. When I put it in the water, these Chinese wolfberry cakes sank obediently.
That's weird. Is that little stick magic? We held our little hands high to try, but the teacher let me go. I picked up a medlar like a red bead and squeezed it hard, huh? Why are there small bubbles? I asked my classmates who came to knead Lycium barbarum with me, and they also found this phenomenon. We quickly asked the teacher for advice, and the teacher solved the mystery for us. It turned out that those small bubbles were produced when air ran out of Lycium barbarum. At first, there was air in Lycium barbarum, so it wouldn't sink in the water. Later, the air inside was squeezed out and then sank into the water. This principle is just like the swimming ring we use when swimming. Ha ha, so that's it!
Today, I learned another scientific truth, and observed while playing in the composition class, which left me an unforgettable impression.
Narrative Composition of Senior Two: An Interesting Experiment 5 Today in the remedial class, the teacher took us to do an interesting experiment.
I saw the teacher take a cup full of water and a paper clip. The teacher said mysteriously, "How many paper clips can overflow the water in the cup?" Will the water in the cup overflow? "As soon as the teacher's words fell, the students blew up. I think it will definitely overflow. As for how much, 60 should be enough.
The experiment began. The teacher said, "Let's play one by one first." I saw the teacher put the paper clip in the cup and bubbles appeared in the water. Like a diver, the paper clip jumped into the water. In this way, 10 was put in a row, and the water did not overflow. Then, we started to put it in pairs, and the water still didn't overflow. I thought: How about playing 10 at a time? I asked the teacher for a 10 paper clip and carefully put it in the cup. At this point, the water has been higher than the cup, but it has not overflowed. The teacher said, "well, I'll put all the paper clips in the water." Do you think the water will overflow? " I thought: that will definitely overflow.
The teacher put all the paper clips in the cup, but the water still didn't overflow. Why is this?
Oh! It turns out that the surface of water has tension. Although the water has reached the mouth of the cup, the water surface can bend due to surface tension.
The cup looks full, but it can actually hold 100 paper clips. It's amazing. I can't help thinking that we are like this cup, and learning is like filling water with a paper clip. It seems full, but it's not. There is no end to learning, which should be the truth.
Narrative composition in the second day of junior high school: an interesting experiment 6. The long-awaited floating needle experiment class is finally about to begin. I saw Mr. Peng give each of us a needle. Seeing this thin and small needle, the excited expression on my face gradually disappeared. Teacher Peng smiled and said, "This is a magical experiment. If everyone's heart is pure, these needles will float on the water. If it is not pure, it will slowly sink to the bottom. " Hearing these words, my curiosity was rekindled.
The experiment officially began, and everyone scrambled to gently put the needles in their hands into the water. The atmosphere was extremely tense because everyone didn't want to be impure, but unfortunately everyone failed. We were not convinced and kept trying, but failed without exception. Some students said that perhaps our posture of putting the needle was not handsome enough, so Li Pingran posed a handsome posture, but the needle simply disdained his handsome posture and still slowly sank into the water. It seems that this method will never succeed!
Just when we were helpless and about to give up. Teacher Peng taught us a magical method, only to see her gently spread a thin piece of paper on the water surface, and then said to us, "1, 2, 3, release!" " "We put on various postures, some casual, some handsome, and some comically put the needle on the paper. After a while, the paper slowly sank, but all the needles floated on the water. " It worked! "Everyone shouted in chorus. Later, Teacher Peng revealed the principle to us. It turned out that water molecules were combined by paper, which made the water have tension, so the needle floated on the water.
There are many unsolved mysteries in the universe, which can only be solved if we are good at observing. Today, we unveiled the mystery of floating needles on water and gave us a unique surprise.
Narrative composition in the second day of junior high school: an interesting experiment 7 "bang", only one sound was heard. "Exploded" It turned out that we were doing a scientific experiment-"Volcanic eruption".
As soon as the bell rang, the science teacher came into the classroom with a big smile on her face and said, "In this class, we are going to do an interesting experiment called' volcanic eruption'. In a short time, the teacher's right-hand man, the squad leader, on behalf of the master, walked towards the science teacher with the step of severing relations with his parents. The class representative swept the students with confident eyes.
The class representative used mashed potatoes to make rocks next to the volcano and tomato sauce to make magma. Then put asbestos net, tripod and alcohol lamp under it, and the preparation work will be completed in a short time.
Next, the science teacher lit the alcohol lamp, and the students held their breath and only heard the sound of zi zi. In a short time, the smell of potatoes drifted away and filled the whole classroom. My stomach growled involuntarily, and I looked at my deskmate. I guess he must be as hungry as I am. Ketchup seems to have been stimulated by someone and turned into a naughty "child", constantly spitting small bubbles, pushing up his mouth full of mashed potatoes and falling to the ground. Ketchup is scattered around mashed potatoes and flows everywhere.
After a while, a big bubble appeared in the tomato sauce and the mashed potatoes began to beat. There was a bang, and ketchup poured out like a flood and splashed all over the podium.
The science teacher told us: "When the underground temperature rises, the magma will expand. When the temperature reaches a certain pressure. Will rush out, this is the so-called "volcanic eruption."
This experiment not only makes us learn knowledge, but also makes me feel that science is everywhere, and I am more interested in science. I believe I will discover more scientific secrets.
Narrative composition of the second day of junior high school: an interesting experiment 8 "Wow, you are amazing, teach me quickly!" " Huh? What is this? It turns out that Teacher Peng took us to do an experiment today-floating needle on water.
After class, Mr. Peng shouted, "If you talk again, believe it or not, I'll throw a basin of dirty water on you and beat you to a drowned rat!" The boys said in unison, "How is that possible?" I saw Mr. Peng come out with a big basin of water in his hand, a small box of needles and a roll of paper. We are all scared like rabbits eaten by tigers.
Teacher Peng changed his face really quickly. He was angry just now, and now he beamed at us and said, "Come on, I'll show you a magic trick." Everyone ran to see it in confusion. Teacher Peng gave everyone a needle and said to the water, "pineapple jackfruit, magic will soon work!" " "Teacher Peng asked us to put the needle on it and see whose needle can float on the water. The boys stuck the needles one by one, but none of them floated. Some needles swim to the bottom like naughty children; Some needles are like drunkards, swaying; Some are like a dancing girl, jumping around. Suddenly, a hand reached out and gently put the needle. The needle actually floats on the water. Everyone shouted: "Wow, who is so powerful? "Everyone is envious. I let it go gently, and it even floated. I am dancing with joy.
Teacher Peng saw that some students still failed to make the needle float, so he said, "I'll tell you two more ways to make the needle float!" " Dry the needle with paper first, then put it on your hair and rub it hard to make it float. Or put a thin piece of paper on the water first, and then put the needle on it to float on the water. "We followed the teacher's method, and sure enough, the needle floated on the water. We chased the teacher and asked, "What's the reason? "
The teacher said, "The second method is the tension of the water surface. Water is like a group of babies, holding hands. When the needle is inserted, the baby can't hold it and the needle falls off. If you put a piece of paper and gather these treasures together, the needle will not fall. "
This experiment is really an interesting experiment, which makes me learn a lot of scientific truth!
Narrative composition in junior two: an interesting experiment 9. I came home from school last Wednesday night. The weather is very hot. I want to have a sprite to cool off. It suddenly occurred to me that I saw an experiment about Sprite in the interesting experimental encyclopedia. I think it must be interesting. I can't wait to try it.
First, I took out a bottle of Sprite. I took out a glass bottle for observation. My mother also prepared a spoon and some sugar for me. Everything is ready, the experiment begins!
I'll take out the Sprite bottle first and pour it into the glass bottle slowly. Transparent sprite braved tiny bubbles and poured it into the bottle, and soon it was half full. Then I put down the Sprite bottle, picked up a spoon and scooped up a small spoonful of sugar, carefully adding it to the bottle. I was about to add the second spoonful of sugar when something incredible happened. Sprite in the glass bottle instantly emitted a large number of bubbles, just like boiling, flowing along the bottle wall to the table.
I think it's amazing! Then I thought, salt and sugar are similar, will the effect be the same? I quickly picked up the salt and tried it. Although there are bubbles, the effect is not as obvious as adding sugar.
Why are there bubbles? It turns out that bubbles in Sprite are carbon dioxide. When sugar is added, it will adhere to the periphery and surface of sugar, resulting in a large number of bubbles. Salt is because the solubility of carbon dioxide in salt water is much less than that in water, so at the moment of adding salt, carbon dioxide runs out of Sprite and becomes bubbles. But I didn't add enough salt, and the effect was not so obvious.
This is really an interesting experiment! It is not only interesting, but also gives me a lot of knowledge. I will do more and more interesting experiments in the future!
Narrative composition of junior two: an interesting experiment 10 "Quiet, let's announce something." As soon as the science teacher's words fell, the classroom was suddenly silent. The teacher said, "The group leaders stand up." Knock, knock, knock, knock, knock I only heard Mr. Wang say, "We are going to do experiments next class. I will arrange the tasks that the team leader must complete. " The leader of one group brought bread, the leader of the second group brought … the leader of the third group brought meat. ..... "The teacher arranged tasks for each group leader. Just then, the bell rang.
Looking forward to the stars and the moon, I finally waited for that science class. Before class, the science teacher asked the students to get many teaching instruments, such as alcohol lamps.
When the bell rang, we hurried into the classroom and did well in our seats. Soon, Miss Wang came to the classroom. The class has begun. Teacher Wang first picked up rice, put it in his hand, made a ball of rice, and then showed it to us. I looked at it. Actually, it's completely different from the previous meal. Incredibly, the rice has turned black now. Then, the teacher dropped a drop of iodine on the steamed bread and showed it to us again. I can't help but be surprised that the place where the teacher dripped iodine on the steamed bread turned blue. The teacher asked us how to tell whether water stains or oil stains were left on the paper. Then he told us how to tell the difference, and how to tell the difference when we were finished. The teacher asked again, "Who can tell whether the cucumber is printed with oil stains or water stains on the paper? Xu Chenyu first broke the cucumber, took the broken end and put a seal on the paper. In the sunlight, we recognized it as water at a glance. This class passed happily. We learned a lot in this lesson, including: how to distinguish oil stains, and what happens when starch meets iodine. ...
This course is really interesting.
Narrative composition in junior two: an interesting experiment 1 1 I went to a composition class today. I felt bored, but I was wrong. It turns out that this is an interesting experiment. The students suddenly boiled and were full of expectations.
I saw the teacher gently pick up a piece of white paper, put it between two boxes and said to us, "Guess what experiment you are going to do today?" We asked doubtfully, "What experiment are we going to do?" The teacher said that we would build a paper bridge today. Then the teacher put the pen on the paper in the middle, and I guessed that the bridge was going to collapse. I frowned and stared at the "every move" of the bridge. Sure enough, the bridge collapsed with a bang. The students sat in chairs and sighed, "Alas, this bridge is too fragile."
Later, the teacher gave each group two boxes, plus five or six pieces of paper, and let us do the experiment ourselves. Let's fold the paper in half first, thinking it will be stronger. Sure enough, a pen fell firmly on the paper, but the paper bridge did not collapse, and I immediately cheered. Look at the other groups, their paper bridges have all collapsed, but mine is very strong. Then I folded it again. Miraculously, all five pens landed safely and smoothly on the paper bridge. This is incredible!
Just as I was triumphant and felt that I was winning, I suddenly found a group of classmates holding some heavy items such as kettles on the paper bridge. I suddenly wondered, how is this possible? After a careful look, I suddenly realized that they folded the paper into a fan shape according to the triangle principle, that is, many triangles were fixed together, which made it stronger. If my paper bridge is like this, it can bear more weight.
Through the experiment of this class, I found that my former self, if you think more about everything, the result will be more perfect and the harvest will be more joyful.
Narrative composition in the second day of junior high school: an interesting experiment 12 friends, do you think it is funny to see this topic? How do you grow sugar? Is it planted in the ground? No, no, no, I'll show you today!
The materials we need to prepare are: a glass bottle with a lid, some fine sugar, a cotton thread, a milk jug and a small piece of rock sugar. I measure this rock candy with a ruler, and the length is about 1. 5 cm, about 1 wide. 2 centimeters.
Start the experiment. First, put the milk pan on the stove, pour in the fine sugar, and heat the fine sugar with the milk pan to completely dissolve it. Then pour the refined sugar solution into a heated glass bottle, yeah! The handle of the milk jug is so hot! I had to hold the handle of the milk jug with a cloth and pour the refined sugar solution into the glass bottle. Finally, the crystal sugar is wrapped with cotton thread, immersed in the solution, and the other end is fixed on the cover, thus, it is finished.
At first, rock sugar was just a small piece. After five days, the rock sugar was bigger than the first day, and the cotton thread was covered with ice-like sugar. It's a pity that the time is not long enough and the rock sugar is not big enough.
Time passed day by day, and finally ushered in the fifteenth day of "planting" sugar. I opened the lid and saw, wow, the rock sugar of fifteen is bigger than five! I measured it with a ruler, and this "big guy" is about 4. 8 cm, about 2 wide. 3 cm, that's amazing.
Why is this? It turns out that rock candy is the crystallization of sugar. When rock sugar is hung in the sugar solution, it becomes the role of "seed" As time goes on, more and more sugar particles in the solution are adsorbed on the "seeds", and the rock sugar becomes bigger and bigger.
Wow, this experiment is so interesting! I want to explore and discover more mysteries in life.
Narrative composition in the second day of junior high school: an interesting experiment 13 "Ding! Jingle bell! When the bell rang, Miss Wang came into the classroom with a big smile on her face. She said to us mysteriously, "Today, Miss Wang is going to do a magic trick for you." Then she took out three pieces of gauze, a lighter, two glasses of transparent liquid, a small clip and a wet rag.
For the first time, the teacher picked up a piece of gauze and said to us, "Students, guess what magical changes will happen to this gauze?" Some people say it will burn out, others say it will burn to ashes. Let's get to know it together! Teacher Wang told us that he was about to light the gauze with a lighter, and soon it burned to ashes.
The second time, the teacher picked up a piece of gauze and swung it back and forth in the first cup of transparent liquid. Students, guess what will happen this time. The students said in unison that gauze would not burn, so the teacher picked up a lighter and prepared to light a fire. But at first, we thought the teacher didn't light the fire. The teacher waved the lighter in front of our eyes and started to light it. It took a long time for the steam to come out and the gauze didn't burn at all.
The third time, the teacher skillfully picked up a piece of gauze, dipped some water in the second cup, and then lit the fire with a lighter. Wow! This time the flame is much bigger than before. The blue flame gradually turned into an orange flame, and suddenly we all stared at the gauze in amazement.
It turns out that the transparent liquid produced for the second time is medical alcohol. Containing 75% alcohol and 25% water will make the gauze burn to produce blue flame, while 25% water is the protector of the gauze and will protect the gauze from being completely burnt.
Life is full of knowledge. As long as we observe life carefully and discover and explore it, we will discover its mystery.
Narrative composition of the second day of junior high school: an interesting experiment 14 Everyone will do many experiments in his life. As long as he observes carefully, we can find out.
During the summer vacation, my mother and I had nothing to do at home, so we started playing table tennis. We were having a good time, and suddenly my mother came with a squat ball. The ball hit me on the forehead with a bang and then fell. I accidentally stepped on a foot, and the table tennis sank into a big block, like a sad doll's head and a deflated balloon. I was so sad that I said to my mother regretfully, "My ball is broken, which is really disappointing. It's all my fault. " Mom saw me like this. Smile and say, "Never mind, I have a way to make it better."
Mother went to the kitchen to boil a pot of boiling water, and the lid kept smoking white. Then she took a teacup and poured half a cup of boiling water. Finally, she put the ball in, pressed the flat place of table tennis with a pair of chopsticks, and let the hot water soak its wound. Sure enough, table tennis slowly unfolded. Finally, there is no trace of stepping on it, and it has returned to its original round appearance. Even whiter and brighter than before, as if it had just been bought. I asked my mother in surprise, "What the hell is going on?" . My mother told me: Because there is air in this table tennis ball, soak it in boiling water and heat it quickly. If the table tennis ball is not broken, the air inside will expand, just like blowing into a balloon, and the ball will be propped up. This is called "thermal expansion and cold contraction", and it is said that these are all physical knowledge, and junior high school teachers will teach us to listen.
In our life, we often encounter many things. As long as we try our best to find a way, observe attentively and do experiments with our knowledge and mind, we will get unexpected surprises, right?
Narrative composition of the second day of junior high school: an interesting experiment 15 In class, Mr. Wu took out a squashed table tennis ball from his schoolbag. Teacher Wu came straight to the point and asked, "Students, how do you play table tennis today?" We said loudly, "Put the ping-pong ball in the hot water.
Teacher Hao said, "Let's do a little experiment today!" So Mr. Wu went to pour a pot of cold water and a cup of hot water. When Miss Wu came into the classroom, we all surrounded her tightly. Teacher Wu carefully put the hot water into the washbasin. We craned our necks and watched intently. Ah, the table tennis didn't turn around. Everyone returned to their original positions in frustration. Teacher Wu smiled and said, "It doesn't matter. Let's try again. We can't fail this time. " At this time, a child volunteered: "Put the ping-pong ball in the cup, and then try pouring hot water into the cup!" " So Mr. Wu did as we said. At this time, the classroom was quiet, and my nervous heart beat faster. I've been thinking about what it will be like this time.
After a while, Mr. Wu opened it and saw that the table tennis really became round. We asked Mr. Wu why table tennis becomes round when it is put in hot water. Teacher Wu said: "Air has the property of expanding with heat and contracting with cold. If placed in hot water, the air pressure inside the table tennis will increase, the table tennis will be pushed out from the inside, and the table tennis will slowly expand.
For example, there are many such examples in life: for example, in summer, the more full the tires of cars and bicycles, the easier it is to have a flat tire. In summer, the wires will be looser, but in winter, the wires will be shorter ... all these are caused by thermal expansion and cold contraction.
How time flies! Soon the bell rang, and through this class, I learned some scientific knowledge.