Place the burned area in cool—not cold—water. It should remain in the water for at least five minutes take the heat out of the tissues. Do not make the water to cold and do not use ice as this may cause further skin damage.
Loosely wrap the affected area in clean, dry gauze to stop the air from hitting exposed nerve endings and to avoid possible infection. Burns can be serious injuries with lifelong impact s If a burn appears to be serious it is important to get professional help.
It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search. Hydrogen is flammable, and for any fire to burn it needs oxygen.
Why does a compound made of hydrogen and oxygen put out fires instead of catalyzing them? I understand that hydrogen and water are chemically different compounds, but what causes water to be non-flammable? You can think of water as the ash from burning hydrogen : it's already given off as much energy as possible from reacting hydrogen with oxygen.
You can, however, still burn it. You just need an even stronger oxidizer than oxygen. There aren't many of them, but fluorine will work,. Water is a product in both of these reactions. Thus, water represents something that has already been oxidized by oxygen, and as such there is little further energetic gain to be made by trying to react it again with oxygen.
This becomes intuitive once you accept that any chemical compound will 'want' to be in the state with the lowest energy, the ground state for a given temperature and pressure. For example, if you plot the energy of the system of two hydrogen atoms against the separation of the atoms, it looks like this:. So back to the question: why does water put out fire instead of catalyzing it? It really depends on what you are burning.
Let's assume it's wood, which is mostly carbon and hydrogen, but for the sake of simplicity, we'll just use methane, which is similar:. The energy released on the right-hand side of the equation is the 'burning'. The ground state of most systems involving carbon, oxygen and hydrogen is some combination of carbon dioxide gas and water. This combination has the lowest energy, and to get anything else, you would have to pump energy into the system. The sodium often burst into fire as it whizzes around the surface of the water, reacting with it to create sodium hydroxide in solution and hydrogen gas that flammable gas.
This is a useful thing to know before you try and put out a fire in a chemical plant or a school laboratory, because it means the throwing water on a blaze could start another fire rather than just putting fires out. But flammable drinking water is a real thing , all the same. Unfortunately, over in China , the pollution of drinking water has led to water coming out of the taps that can be burned! That the pollutant is an oil is important because oils are not miscible with water they separate into a different liquid layer rather than mix with the water and thus the oil burns on top of the water and not in it.
This may require the absolute immersion of the burning item in water so that the water makes a seal against oxygen being used by the fire or it may be used to cool the fire and allow the heat to be leached out of it by the cold water.
Firstly, if one of the substances that burn in water such as sodium or powdered magnesium is present, you might extinguish one blaze but start another. Technically, if you were to immerse a grease fire completely in water, then it would be extinguished due to lack of oxygen.
In practice, it is a very, very bad idea to try and extinguish a grease fire with water. Watch as this restaurant employee tries to put out a fryer fire with water:. When the water hits the grease, it creates little droplets of grease that are still burning, and which get sprayed everywhere. Adding water to an oil fire is asking for a much bigger, much more dangerous blaze.
Instead use a dry chemical fire extinguisher that is rated for class B or K fires. We've all been there.
I can count at least five times I've overcooked something to the point that it burns. It's never a pretty site. But there are ways to prevent things from burning.
Use quality cooking dishes. You might think that there isn't really a difference between high quality pots and pans and cheaper pots and pans, but there are and you should splurge a bit to get the better quality dishes.
Use nonstick pots and pans. If you don't have them use cooking spray or something to prevent sticking. Clean your stovetop and wipe down the exterior of your pots and pans before cooking. Preheat the oil before adding the food. Use a burner that fits your pot and pan. When cooking sauces heat them slowly and stir often. Rotate your pot or pan.
When baking, test the time it takes to bake the recipe.
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