Experiment one. Make carbon dioxide and test some properties of carbon dioxide?
Experimental steps:
1. Take a small test tube, drop a small amount of litmus test solution (the rubber dropper must be hung vertically above the test tube mouth), and then put the test tube containing litmus test solution on the test tube rack for later use; ?
2. Take a large test tube horizontally, put 2-3 marbles at the mouth of the test tube with tweezers, and then slowly erect the test tube to make the marbles slide to the bottom of the test tube; ? 120
3. Take dilute hydrochloric acid, put the cork upside down, with the label facing the palm of your hand and the mouth of the container beside it, so that dilute hydrochloric acid can be slowly added to the test tube filled with marble, and the dosage of hydrochloric acid should not exceed one third of the volume of the test tube (the cork should be covered immediately after adding hydrochloric acid, and reagent bottle should be put back in its original place), then plug the rubber plug, fix the test tube on the iron frame, and the iron clip is clamped on the upper part of the test tube; ?
4. Introduce the generated carbon dioxide into litmus test solution until it turns red (observe the phenomenon); Take out the small test tube containing the red litmus test solution, clamp it from bottom to top at one third of the test tube mouth, light the alcohol lamp, preheat it first, and then heat the medicine part. The test tube forms an angle of 45 with the desktop, and the mouth of the test tube is not allowed to face people, and it is heated until the red solution turns purple (observe the phenomenon); ?
5. Pour all the garbage into the garbage can, clean the glass instruments and put them in order, and wipe the desktop clean.
Report: Is the experiment over?
Experiment 2, filtration of crude brine?
Experimental steps:
1. Take a piece of filter paper, fold it in half twice, open it into a cone, and put it in the funnel with the tip down. Add a little steam to the filter paper.
After the distilled water is moistened, gently flatten it with a glass rod to make the filter paper stick to the funnel. ?
2. Put a small beaker under the iron ring of the iron frame, and then put the funnel on the iron ring, and the tip of the lower end of the funnel is close to the inner wall of the beaker. ?
3. Gently contact one end of the glass rod with the third layer of the filter paper, and put the beaker mouth filled with crude brine near the glass rod to drain the liquid. After use, clean the glass rod in time and put it back in its original place, and the liquid level shall not exceed the edge of the filter paper?
4. Pour all the waste into the waste box, clean the glass instruments and put them in order, and wipe the desktop clean.
Report: Is the experiment over?
Experiment 3: 50g 1% sodium chloride solution was prepared with 5% sodium chloride solution.
Experimental steps:
1. Pour 8-9 ml of sodium chloride solution into the 10ml measuring cylinder (put the cork upside down, with the label facing the palm of your hand and the container mouth beside it, and use it up.
Put reagent bottle back immediately after covering the cork), put the 10ml measuring cylinder flat on the experimental platform, and add it drop by drop with a rubber-tipped dropper (the dropper is suspended directly above the measuring cylinder and cannot be extended) to 9.7ml (the line of sight and concave liquid level are kept at the lowest level). Pour the measured solution into the beaker, immediately clean the rubber dropper and put it back into the small beaker for later use. ?
2. Pour 38-39 ml distilled water into a 50ml measuring cylinder (the bottle stopper is upside down, the label is facing the palm of your hand, and the container mouth is beside it. Immediately after use, cover the cork, and reagent bottle put it back), then put the 50ml measuring cylinder flat on the experimental platform, add it to 40ml drop by drop with a rubber dropper, then pour the measured liquid into a beaker, and immediately clean the rubber dropper and put it back. ?
3. Stir evenly with a glass rod (stir slowly without touching the inner wall of the beaker). ?
4. Pour all the waste into the waste box, clean the glass instruments and put them in order, and wipe the desktop clean.
Report: Is the experiment over?
Experiment 4. What are the chemical properties of metals?
Experimental steps:?
1. Take a piece of copper in a crucible, burn it in an alcohol lamp until it turns black, and then put the heated copper on an asbestos net. ?
2. Take a test tube horizontally, put an iron nail into the mouth of the test tube with tweezers, and then slowly erect the test tube so that the iron nail slides to the bottom of the test tube. Take copper sulfate, turn the cork upside down with the label facing the palm of your hand, and slowly pour copper sulfate into the test tube next to the container mouth with a nail. The dosage of copper sulfate shall not exceed one third of the test tube volume (the cork shall be covered immediately after use, and the reagent bottle shall be reset). Observe the phenomenon. ?
3. Take the other two test tubes and place them horizontally. Clamp the copper and zinc particles with tweezers, put them at the mouth of the test tube, and then slowly erect the test tube so that the copper and zinc particles slide to the bottom of the test tube. Drop dilute hydrochloric acid into two test tubes respectively, and the rubber-tipped dropper must be hung vertically above the test tubes to observe the phenomenon. ? 4. Pour all the waste into the waste box, clean the glass instruments and put them in order, and wipe the desktop clean.
Report: The experiment is over. ?
Experiment 5. What are some chemical properties of acids and bases?
Experimental steps: 1. Take a small amount of solution A in test tube A, and then take a small amount of solution B in test tube B (put the cork upside down, with the label facing the palm of your hand and the mouth of the container next to it, immediately cover the cork after use, and put reagent bottle back in its original place? ), drop a few drops of phenolphthalein solution into test tube A and test tube B respectively (the rubber-tipped dropper is hung vertically above the test tube mouth), so that the phenolphthalein solution turns red with the alkali solution; ?
2. Drop a small amount of dilute hydrochloric acid into the test tube that turned red in step 1 until it is colorless, and hang the rubber-tipped dropper vertically above the test tube to observe the experimental phenomenon; ?
3. Take a small amount of solution A from the test tube (the cork is upside down, the label is facing the palm of your hand, and the container mouth is beside it. Immediately after use, put the cork on and put reagent bottle back? ), dip a small amount of solution A into the test tube with a glass rod and drop it on the pH test paper. Compare the test paper with the colorimetric card to get the pH value of solution A, clean the glass rod in time and put it back. ?
4. Pour all the waste into the waste box, clean the glass instruments and put them in order, and wipe the desktop clean.
Report: The experiment is over.