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Burns in chemical experiments refer to local injuries to the body caused by strong acids, strong bases, and certain poisons coming into contact with the skin or exposed organs. If not treated promptly, these burns can often lead to necrosis of tissues and organs, leaving burn scars. Burns are a common safety accident that occurs during chemical experiments. For example, when alkali metals, bromine, phosphorus, concentrated acids, concentrated alkalis, or other irritating substances get into the eyes, they can cause burns to the eyes ； Acids that come into contact with the skin can cause burns; for example, hydrofluoric acid can erode nails and bones. When it comes into contact with the skin, it causes painful, hard-to-heal burns. There are also alkali burns, bromine burns, etc.; these are very dangerous. Wounds caused by bromine burns generally do not heal easily, so strict precautions must be taken. Additionally, it is easy to get burned when melting and working with glass items, and cuts can easily occur when cutting glass tubes or inserting thermometers, glass tubes, and other items into corks or rubber stoppers. Therefore, during chemical experiments, we must follow standard procedures, be extremely careful, take preventive measures, and try our best to avoid burns. Once a burn accident unfortunately occurs, we should not panic; instead, we must immediately take scientific and appropriate emergency measures. Depending on the type of chemical that caused the burn, the severity of the burn, and the location of the burn, we should take different first-aid measures. Prevention of burns: 1. The most important thing is to protect your eyes! Goggles (with plain glass or plexiglass lenses) should always be worn in a chemistry laboratory to protect the eyes from irritating gases and to prevent any chemicals, especially strong acids, strong bases, glass shards, and other foreign objects, from entering the eyes. 2. It is prohibited to pick up any chemical substances with bare hands. When using **, rubber gloves must be worn in addition to spatulas and measuring devices; after the experiment, clean the instruments and equipment immediately, and wash your hands with soap right away. 3. Try to avoid inhaling any vapors of medications or solvents. When handling irritating, foul-smelling, and toxic chemicals such as H2S, NO2, Cl2, Br2, CO, SO2, SO3, HCl, HF, concentrated nitric acid, fuming sulfuric acid, concentrated hydrochloric acid, acetyl chloride, etc., it must be done in a fume hood. Do not stick your head into the fume hood once it is turned on, and ensure good ventilation in the laboratory. 4. The use of cyanides in acidic media is strictly prohibited. 5. It is prohibited to use a mouth straw to draw up concentrated acids, concentrated alkalis, or toxic liquids; instead, a ear syringe should be used. It is prohibited to recklessly taste chemical reagents; one must not sniff gases directly with the nose, but instead fan a small amount of gas toward the nostrils with the hand. 6. Do not wipe medications that have spilled on the skin with organic solvents such as ethanol, as this will instead increase the rate at which the skin absorbs the medication. 7. Smoking and eating are prohibited in the laboratory, as are wearing sleeveless clothes and slippers. First aid measures for burn injuries: 1. Alkali burns – Strong alkalis are highly corrosive and irritating; once skin is burned by an alkali, it should be immediately rinsed with plenty of water until the alkaline substance is almost completely removed, after which it should be rinsed further with a 1%–2% acetic acid solution or a 3% boric acid solution. When the eyes are burned by alkali, they should first be rinsed thoroughly with plenty of running water, followed by irrigation with an appropriate neutralizing solution such as a 2%–3% boric acid solution; special care must be taken to ensure thorough rinsing of the fornix area. 2. Acid burns: Common strong acids such as sulfuric acid, nitric acid, and hydrochloric acid all have strong irritant and corrosive effects. Skin burns caused by sulfuric acid usually appear black ； Nitric acid burns appear grayish-yellow ； BURNS FROM HYDROCHLORIC ACID ARE YELLOW-GREEN IN COLOR. Immediately after the skin is burned by acid, rinse it thoroughly with plenty of running water. (When the skin is contaminated with concentrated sulfuric acid, do not rinse it with water first; otherwise, the exothermic reaction that occurs during the hydration of sulfuric acid may worsen the injury. Instead, use a dry cloth to absorb the concentrated sulfuric acid first, and then rinse with water.) After thorough rinsing, neutralize the area using a 2–5% sodium bicarbonate solution, dilute limewater, or soapy water. Never use alkaline substances to neutralize on the skin without first thoroughly rinsing it with plenty of water, as this will worsen skin damage. If a strong acid gets into the eyes, it is necessary to immediately rinse them thoroughly with plenty of clean water or saline at the scene. When rinsing, the head should be held under the faucet so that the water flows away from the temporal side of the affected eye; this prevents the water from directly hitting the eyeball while also stopping the acidic solution from reaching the healthy eye. The upper and lower eyelids should be kept open during rinsing to ensure that the acid does not remain inside the eye or in the inferior fornix. If no rinsing equipment is available, immerse the eye in a basin of clean water, pull down the lower eyelid, and move the head to wash away the acid. Do not close the eyes due to pain; after performing these steps, seek immediate treatment at an ophthalmology department. 3. Bromine burns: Liquid bromine and bromine vapor are highly irritating and corrosive to the skin and mucous membranes. Contact of liquid bromine with the skin causes pain and can lead to difficult-to-heal wounds; in severe cases, it can cause skin ulcers. Bromine vapor can cause tearing, coughing, dizziness, headache, and nosebleeds; in severe cases, it can be fatal. When bromine burns the skin, rinse it first with plenty of water, and then wash and bandage it with a mixture of 1 volume of ammonia solution (25%), 1 volume of turpentine, and 10 volumes of ethanol (95%). If bromine vapor is inhaled accidentally, ammonia and fresh air can be inhaled as a means of detoxification. 4. White phosphorus burns: Once phosphorus enters the body through the skin, it accelerates the excretion of calcium from the body, leading to bone decalcification. It can also inhibit the body’s oxidation processes, resulting in disorders in protein and fat metabolism. When the skin is burned by white phosphorus, promptly remove any contaminated clothing and immediately rinse the area with clean water. Then, soak it in a 2% sodium bicarbonate solution to neutralize the resulting phosphoric acid. Next, gently apply a 1% copper sulfate solution to the wound; this causes any remaining white phosphorus on the skin to form insoluble copper phosphide, thereby preventing further absorption of white phosphorus by the skin. Finally, apply a wet compress made from 0.1% potassium permanganate and bandage the area. The wound must not be exposed to air, and no oily substances should be applied to it. 5. Phenol burns: Once phenol enters the body, it spreads to tissues throughout the body and penetrates cells, causing systemic toxic symptoms. Phenol directly damages the myocardium and capillaries, leading to deformation and necrosis of the myocardium. When the skin is burned by phenol, it should be wiped several times with 30–50% alcohol immediately, then rinsed thoroughly with plenty of water. After that, a saturated solution of sodium sulfate should be applied as a compress for 4–6 hours. Since diluting phenol with water at a ratio of 1:1 or 2:1 can instantly worsen skin damage and increase phenol absorption, the affected area should not be rinsed with water first. 6. Trauma such as burns and cuts: Burns are most likely to occur when melting and processing glass items ； Cuts are most likely to occur when cutting glass tubes or inserting items such as thermometers or glass tubes into corks or rubber stoppers. In case of an accidental cut, first remove any foreign objects such as glass fragments from the wound. Wash the wound with water, squeeze out a little blood, apply mercurochrome solution, and then bandage it with sterile gauze. A \"band-aid\" can also be applied to the cleaned wound; it stops bleeding immediately and promotes faster healing. In the event of a severe cut that causes heavy bleeding, it is necessary to stop the bleeding first. Lay the injured person down flat, elevate the area where bleeding is occurring, apply pressure to the nearby arteries, or use a bandage to cover the wound and apply direct pressure. If the bandage gets soaked with blood, do not replace it; instead, place another bandage on top to continue applying pressure, and seek medical treatment immediately. Once burned by flames, steam, red-hot glass, iron, etc., the wound should be immediately rinsed or soaked in plenty of water to rapidly cool it down and prevent thermal burns. If blisters form, they should not be punctured; instead, they should be covered with gauze and taken to the hospital for treatment. For minor burns, apply some cod liver oil or burn ointment or camphor oil to the affected area and then cover it with a bandage.