初中化学趣味小实验（Small interesting experiment of chemistry in junior high school）

初中化学趣味小实验（Small interesting experiment of chemistry in junior high school） 初中化学趣味小实验(Small interesting experiment of chemistry in junior high school) ["coke" "Sprite"] Coca-Cola and Sprite are the ideal summer drink. Coca-Cola is light brown liquid, and Sprite. It is a clear and transparent liquid. Here is a "Coca-Cola" into a "small experiment of Sprite. Take one empty Coca-Cola bottle and pour 3/4 volumes of distilled water. Take a beaker with 50 ml of alcohol, and adding proper amount of iodine, iodine alcohol solution prepared with dark brown. The solution with a good bottle, until the color of the solution side edge oscillation and coke are similar so far. A bottle of coke is ready. In the sodium thiosulfate in the dry cap (soda) powder, and then take a piece of paper cover, glutinous rice powder, and the bottle cap on the bottle lid gently, carefully covered tightly, do not pay attention to soda powder scattered in the bottle. Coca-Cola will soon shake a bottle, a bottle of "delicious" into a colorless and transparent "Sprite". It turns out that sodium sulfide and iodine can undergo oxidation reduction reactions and fade out the color of iodine solutions: I2+2Na2S2O3===2NaI+Na2S4O6 Naturally, this "Coca-Cola" not delicious, "Sprite" is not refreshing, they absolutely can not drink. [black paper on black] Take a sheet of white paper and write the word "Chemistry" on the white paper with dilute sulfuric acid because the dilute sulfuric acid is colorless Bright liquid, so you can hardly see the writing on the white paper, but dry the white paper on the white paper The surface becomes "Chemistry" black words. What's the point, please? Answer When the dilute sulfuric acid is dried on the white paper, the dilute sulfuric acid is turned into concentrated sulfuric acid because of the reduction of water content, One characteristic of concentrated sulfuric acid is that it can make organic matter carbonized. The main component of the white paper is made from cellulose (organic) composition, the paper concentrated sulfuric acid dehydration carbonization, the office place into a charred, originally written in "chemical" word goes out. [magic wand lighting] Can you use a glass stick instead of a match to light an alcohol lamp? The answer is yes. Experiment: take a small amount of Potassium Permanganate crystals on the surface plate (or glass), in Potassium Permanganate 2 drops and 3 drops of concentrated sulfuric acid are dipped in glass rods to contact the wick of the alcohol lamp. The alcohol lamp is lit immediately. The monkey changes under the magic wand "On the next show, the monkey changes a snake under the magic wand. It is performed by the chemistry team teacher zhang." The announcer As soon as his voice fell, thunderous applause broke out at the stage. Then, Zhang walked over fifty years Go to the podium, his right hand holding a white jade crafts monkey, a left hand two The length of the length of the glass bar, so that the audience to see, then put monkeys on the stage. And then use glass One end of the glass rod gently place a small monkey head, the miracle appeared immediately: suddenly, monkey L smoke fire, into a meandering Yellow snake, sky vertical, assumed to attack the enemy He was amazed by his posture and his wonderful performance. It is true that except for the skill of teacher Zhang Besides, there must be some tricks. Please think it over. Where is his secret? Answer It turned out that the little monkey was made of a material called mercuric cyanide. Its method is: Take the right amount of mercury thiocyanate, a little water, trace the glue, add some sugar and potassium nitrate, the cohesive material, a monkey, to be dry after the performance. Before the performance, the head will drill a small hole, and then drops into a few drops of alcohol. One end of the glass rod pre dipped in some concentrated sulfuric acid and the mixture of Potassium Permanganate, because Potassium Permanganate has oxidizing, mixed and concentrated sulfuric acid, strong oxidizing and burning. So, just place the monkey's head lightly, and the alcohol burns, and then the monkey begins to burn because it contains potassium nitrate, which releases oxygen when heated, So the burning fire. Because of the enormous expansion of mercury when Mercury is heated, a curved yellow long snake rises. But when a snake happens, there is an unpleasant smell. Be careful not to get it to your mouth. [strange programs] As soon as the bell rang, the Spring Festival Gala began. The announcer with a special method to the audience announcer, he saw the hands hold the spray, on a piece of paper a spray, white immediately the scarlet letter: dazzlingly beautiful first show "strange program", also appeared in other shows. The announcer's brilliant performance won warm applause from the audience. But one of the small audiences raised a question: How did the strange program of the white letter of the scarlet letter appear? Dear reader, can you give an explanation? Answer It turned out that the strange program was based on the chemical reaction principle. This process is, first with phenolphthalein solution colorless in the white paper, write the words hanging in the announcer, and then spray will spray a colorless sodium hydroxide solution to the paper, they combine into red.