Chemistry is everywhere

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You probably agree with me on the first fact: chemistry is fascinating . There are plenty of unanswered mysteries within this science, but there are also many interesting and fun chemistry facts . We have some fun and interesting facts from the world of chemistry for you. Some of them have an impact on our everyday life, while others are just fun to know about.

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Lightning strikes produce Ozone, hence the characteristic smell after lightning storms Удары молнии производят озон, следовательно характерный запах после грозы Ozone, the triple oxygen molecule that acts as a protective stratospheric blanket against ultraviolet rays, is created in nature by lightning. When it strikes, the lightning cracks oxygen molecules in the atmosphere into radicals which reform into ozone. The smell of ozone is very sharp, often described as similar to that of chlorine. This is why you get that “clean” smell sensation after a thunderstorm.

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The only two non-silvery metals are gold and copper Единственными двумя несеребряными металлами являются золото и медь A metal is an element that readily forms positive ions ( cations ) and has metallic bonds. These elements have electrons that are loosely held to the atoms, and will readily transfer them. This is why metals are great electrical and thermal conductors — because the electrons move energy. Most metals’ electrons reflect colors equally, so the sun’s light is reflected as white. Gold and copper, however, happen to absorb blue and violet light, leaving yellow light. It’s worth noting here that copper is also the only metal that is naturally antibacterial.

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Water expands when freezes, unlike other substances Вода расширяется при замерзании, в отличие от других веществ Typically, when something is cold, it shrinks. That’s because temperature describes atomic vibration — the more vibration, the more space it takes, hence expansion. Water is an exception. Even though it vibrates less when it’s frozen, the ice occupies more volume. That’s due to the strange shape of the water molecule. If you remember your Chemistry 101, the water molecule looks like Mickey Mouse, the oxygen atom sitting at the center (the face) and two hydrogen atoms each at an angle (Mickey’s ears). Because of how oxygen and hydrogen bond, the water molecule is an open structure with a lot of space. When water freezes it releases energy because a lot of extra strong bonds can be made. But it does take up more space. And so, ice expands when it freezes. Another interesting fact worth mentioning is that hot water freezes faster than cold water.

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If you pour a handful of salt into a glass of water, the water level will go down Если вы насыпаете горсть соли в стакан воды, уровень воды понизится When you step inside a bathtub, the water level will immediately go up, per Achimedes ’ law. But when you add a volume of sodium chloride (salt) to a volume of water, the overall volume actually decreases by up to 2%. What gives? The net reduction in observed volume is due to solvent molecules which become more ordered in the vicinity of dissolved ions.

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Diamond and graphite are both entirely made of carbon and nothing else Алмаз и графит полностью состоят из углерода и ничего больше Though made of the same stuff, the difference between a crown jewel and pencil lead is given by form. Namely, diamond and graphite are arranged differently in space making them allotropes of carbon.

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Your car’s airbags are packed with salt sodium azide , which is very toxic Подушки безопасности вашего автомобиля упакованы с азидом натрия соли, который очень токсичны й When a collision takes place, the car’s sensors trigger an electrical impulse which in the fraction of a second dramatically raises the temperature of the salts. These then decompose into harmless nitrogen gas, rapidly expanding the airbag.

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Where Did Most of the Oxygen in the Atmosphere Come from? Откуда Взялась Большая часть Кислорода в Атмосфере? Surprisingly, 20% of the world’s oxygen is produced in the Amazon Rain forest. This is the largest rainforest on Earth. Its Basin covers 40% of the South American continent.

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What Are Olympic Gold Medals Made Of? Из Чего Сделаны Олимпийские Золотые Медали? They Olympic gold medals are not completely made of gold. In fact, they are made of at least 95% of silver, containing a minimum of 6 g of gold. Gold is much more expensive than silver. However, thanks to this “tricky” alloy, a golden medal is just worth about $550, while silver medal is around $300. Gold is around 100 times more expensive than silver, so a full-gold Olympic medal would cost $30.000! That’s why they only add enough amount of gold to give the medal the characteristic golden color. A bronze medal, made of cheap copper and zinc, is actually worth only $2.

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Why Does Ice Float on Water ? Почему Лед плавает на воде? Ice floats on water because it is the least dense of the two. As a general rule, out of two different substances or materials that do not react with each other, the less dense will float on top of the denser. The density of ice is around 10% lower than the one for water. This property is extremely important for life. Rivers and lakes freeze from the top, so animals can still survive in the liquid water below. If ice was denser than water, it would sink, displacing water to the top, freezing as well as a result. This would result on the whole river/lake freezing, killing most forms of life living within.

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Why Do We Put Salt Into Icy Roads ? Почему Мы Кладем Соль На Обледенелые Дороги? This is due to colligative properties, specifically freezing point depression . When dissolving a salt, such as NaCl , in water, we can make its melting point go down from 0 ºC all the way to -20 ºC, or lower. This way, water will stay in liquid form even at sub-0 ºC temperatures, getting rid of ice on the roads.

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Как Гелий Меняет Ваш Голос? How Does Helium Change Your Voice? Sound travels though helium, a lighter gas, much faster than it does through air, a heavier gas. Sound travels around 2-3 times faster through helium, making high frequencies sound louder than low frequencies, making your overall voice sound higher in a funny way. If you were to do the opposite: inhaling a gas denser than air, the effect would be your voice sounding lower for the exact same reason.

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Why Do Fresh Eggs Sink, and Rotten Eggs Float? Почему Свежие Яйца Тонут, а Тухлые Плавают? A classical trick to know whether we can still eat an egg (if they are fresh enough) is putting them in a bowl of water. If the egg sinks, it means that it is still denser than water, which is the natural state if they are still fresh. As decomposition takes place, solid and liquid matter is transformed into gas. Gaseous pressure builds up, and since the egg shell is porous, this gas starts escaping. This loss of mass, eventually leads to the density of the egg being lower than water’s. This makes the egg float. This represents an easy way to tell if an egg has undergone too much decomposition to be eaten (if it is rotten).

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Нужно ли Лягушкам пить? Do Frogs Need to Drink? Frogs do not need to drink using their mouths. The absorb water through their skin. They have a skin-area called “drinking patch”, on their bellies, which they use to get all the water they need.