The name of the experiment is * * * * Eggs get fat. The materials are eggs, vinegar and cups. As long as the egg is soaked in vinegar for 3 days, the eggshell will become soft and its volume will increase by 1.5 times.
On the first day, I carefully observed the egg and found that there were bubbles on the egg and the color of the egg changed.
The next day, I found many cracks on the eggs, and there were big and small bubbles on the vinegar.
On the third day, I observed that the shell of the egg was gone, and I found that the egg had really become fat.
After doing this experiment, I also understand its principle. The white eggshell disappeared because it was dissolved by acetic acid. The main component of eggshell is calcium carbonate, and the bubbles in eggshell soaked with vinegar are carbon dioxide bubbles produced by dissolution reaction.
Do you know, children?
2. Pupil Composition: An Interesting Experiment [Pupil Composition: An Interesting Experiment] Pupil Composition: An Interesting Experiment Text: From Grade One to Grade Four, science has always been my favorite subject. Pupil Composition: An interesting experiment. I have done countless experiments in science class, but among these countless experiments, the only one I remember vividly is the coin experiment I did not long ago. \ x09 \ "yeah!" As soon as the voice fell, the students cheered. "Is it an experiment of throwing coins into the water?" A classmate prophecy. "that's right! Who has a coin around you? " "My coins?" "I! Me! I have! " Students are scrambling to "hand in" their coins one after another. The third grade composition "Elementary School Students' Composition: An Interesting Experiment". \x09 \x09 The experiment started, and the teacher threw coins into the full glass. I squeezed in front, staring at the glass with my eyes wide open, for fear of missing any tiny link. "One, two, three ..." "The water will overflow!" The students said in unison. "Wrong! Let's continue to look down! " "Who has any coins?" The teacher "searched" six coins from his classmates and carefully put them into the water one by one. After the last coin "plopped" into the water, like a well-trained diver, it turned 360 degrees in the water before falling into the bottom of the cup. \x09 \x09 At this time, the students were surprised to find that the water surface actually exceeded the mouth of the cup, and it was half a centimeter! The students immediately surrounded the teacher and asked what the reason was, but the teacher bought a pass and asked us, "What do you think?" We are all monks-puzzled. After repeated inquiries from our classmates, the teacher finally opened the "golden mouth" and mysteriously said, "This is the tension of the water surface. It is this invisible force that supports the water surface beyond the cup mouth without overflowing." So it is! We finally understand the truth. \x09 \x09 This experiment has taught us that we can't make arbitrary conclusions about everything, but we must be brave in exploration and practice to solve the mystery. There are still many secrets in nature, and I believe that as long as we keep exploring, we can solve many mysteries. \x09 \x09 Instructor: Wu Yan \x09 \x09.
3. The experimental primary school composition in my heart is 350 words [the experimental primary school composition in my heart is 350 words] I have been in the experimental primary school kindergarten since I was three years old. Every day when my grandfather sends me to kindergarten, I pass the experimental primary school composition in my heart is 350 words. I see that the building in the experimental primary school is too high, and the stairs alone are two stories high. There is a tall flagpole in front of the building. I also saw many students watching the national flag being raised around the flagpole, and sometimes I saw my brothers and sisters standing in neat teams and dancing in uniform uniforms. My mother said that they were dancing in the national standard, and the music played on the radio was also very nice. The composition in the third grade of primary school was "350 words of experimental primary school composition in my heart". One day, when I was a freshman, I just arrived at kindergarten, and the old teacher told us to stand in a neat team. We are going to visit the experimental primary school. The campus of the experimental primary school is too big, and many flowers and trees are planted. There are big blackboards, many desks and many paintings on the walls in the classroom. There is also a classroom specially for us to do experiments by ourselves! The teachers here are very kind, and my brothers and sisters are also very polite. I like this school very much. My mother said that I would really start from here and prepare a brand-new schoolbag for me. I will definitely study hard. Now I'm looking forward to growing up and going to the experimental primary school soon. I'm studying in Class 2, Shi Xiao Kindergarten: Chen Guanbing, May 9, 2008.
4. How should I write the materials for the third grade of primary school? As the saying goes, "The phoenix will be reborn from the ashes." Only after the body has undergone heavy pain and tempering can the phoenix be reborn with a better body. People are the same. To gain the added value of life, only through constant tempering.
Topic expansion: value, sacrifice, facing difficulties
A famous speaker gave an inspirational speech to the fresh graduates of a university. The college students were very excited when they heard the news, and came to the auditorium early to grab seats. College students who are about to embark on the society are full of ambitions, hoping to get some useful teachings from the speakers.
The speaker arrived as scheduled, with a balance in his hand, stepped onto the platform with dignity and looked around in a friendly way. The auditorium was suddenly quiet, and the college students watched the speaker curiously. Everyone is a little puzzled, why do you bring a balance to the speech? At this time, the speaker said, "Today, I'm going to do an experiment that I have done in junior high school chemistry class. Which classmate would like to be my assistant? " Everyone raised their hands one after another. The speaker chose the classmate sitting in the front, then held up a slender thing and said, "This is the familiar magnesium bar. Please ask my assistant to weigh its quality. " The classmate weighed the magnesium bars according to the requirements of the speaker. After weighing, the speaker lit the magnesium bar.
After the magnesium bar burned, it turned into magnesium oxide, and the speaker called the assistant to weigh it. As a result, the quality of a magnesium bar increased. At this time, the speaker said earnestly: "People are just like that magnesium bar, only when they burn will they have weight." After speaking, the speaker bowed and left the auditorium.
The college students sat there stupefied, dumbfounded. After a while, thunderous applause rang out in the auditorium.
5. Unit 4, Book 1, Grade 3 I did a little experiment to write the first part. I can write some sentences about science, and I can also explain why you did this little experiment and what is the name of your experiment.
In the second part, you can write about your preparation process. For example, list your experimental materials in detail.
The third part, the detailed part, mainly writes about your experimental process. In this part, besides writing the process clearly according to the experimental steps, if you want to write vividly and brilliantly, you should write detailed descriptions of specific actions, demeanor and psychology.
For example, how to overcome difficulties, how to change psychology, and how to feel successful in the experiment. The fourth part is the summary part.
Summarizing the harvest of this experiment can be the joy of success, or it can be some truths that are understood. For example, success in science lies in not being afraid of failure and being persistent. Examples of small experiments are: writing secret letters skillfully, candles in water.
6. Composition Writing in Grade Three Experimental Primary School Small Campus Big Society 400 Our campus is very small, and there is neither a wide playground nor a tall gymnasium. But every morning when I walk into the campus and see the striking school motto of "Civilization, Health, Diligence and Innovation" on the teaching building, I think that our campus is small, but as long as we follow the requirements of the school motto, we can walk out of a vast world and become a pillar of society in a small campus. \x09 \x09
Civilized language and civilized manners are good qualities that we should have since childhood. Treating everyone with a kind and sincere heart, starting from little things and starting from small things, civilization will become a good habit in our life.
In the garden, the students' rules are often echoed, and we have learned a lot of principles and requirements of being a man in a subtle way, which has laid a solid foundation for our future development. \x09
A healthy body and a healthy mind are important conditions for us to do well in our studies. Interesting events such as long-distance running in winter, skipping rope and shuttlecock kicking competitions make us fall in love with sports and strengthen our physique. Activities such as spring outing, autumn outing, visiting museums and underwater world broaden our horizons, increase our knowledge, and make us more cheerful, optimistic and full of sunshine. \x09 \x09
Diligence is the only way for us to succeed. Only by diligence can we make continuous progress in our studies. We not only admire the brilliant achievements made by great scientists and artists, but also see their hard work and sweat behind these achievements. We should cherish good times, study hard and master more scientific and cultural knowledge. \x09 \x09
Innovation is our goal. We should make use of the knowledge we have learned, give full play to our imagination, let our dreams have scientific wings, and turn today's fantasy into tomorrow's reality. \x09 \x09
Our campus is small and our ideals are great.
7. How to write the experimental composition "Volcano Eruption" in the third grade of primary school? Add anthropomorphic sentences and figurative sentences. The word "volcano" erupted _350 words.
Objects always have certain properties, either acidic or alkaline.
Once I mixed acidic vinegar with alkaline baking soda. Suddenly there was a violent chemical reaction between them. In an instant, the mixture turned into carbon dioxide foam and swelled up. According to this principle, I am going to make an artificial volcanic eruption.
I put a lot of baking soda powder in a big bottle, and then put the bottle into a pile of sand hills, and the bottle mouth just emerged from the top of the mountain, which is the "crater". Then, I poured a little hydrochloric acid into the cup and a lot of vinegar, and the preparation was finished.
I poured acid into the crater through a tube. In an instant, the bottle sizzled. The volcano erupted. "Magma" soared into the sky in a column shape, "volcanic ash" sprayed everywhere, and "magma" flowed down the hillside. In a short time, the "magma" was sprayed out and the "volcano" was calm.
Haha, interesting! This is the general situation of artificial small "volcano" eruption In fact, this reaction of acid and alkali has a great effect! Carbon dioxide fire extinguisher is the use of weak acid and weak base reaction to produce carbon dioxide.
Do you want to witness the volcanic eruption with your own eyes, then you can try it.