Like physics, mathematics, geometry – chemistry is a rather complex science. And it’s safe to say that there are not so many students in schools, colleges and institutes who like this subject. But no matter how complicated chemistry may seem, it is a very exciting and interesting science.
And today we have prepared for you a number of interesting facts about chemistry, which should please not only children, but also an older audience.
The only solid elements that can be in liquid form at room temperature are bromine and mercury. There is another solid element that can take on a liquid form if you take it in your hand. This is gallium.
Unlike most other substances, which shrink when freezing, water, on the contrary, expands. An ice cube takes up approximately 9% more volume than the water from which it was formed.
If you take a liter of alcohol and a liter of water, then the resulting volume of liquid will not be 2 liters. It’s a paradox, because if we mixed 1 liter of water and 1 liter of water, we would get exactly 2 liters of water. But why doesn’t this work with alcohol? The thing is that when alcohol and water are mixed, the so-called contraction (Latin Contractio) occurs, the contraction of the volume of the solution due to the interaction of alcohol and water molecules.
The most abundant element in the universe is hydrogen. It is also the first element in Mendeleev’s Periodic Table. The Universe is 92% by the number of atoms and 75% by mass composed of this chemical element. The second most abundant element in the universe is helium. It accounts for about 23% of the entire mass of the Universe. All other elements take up only 2%. As for our planet, the most common elements in the Universe are not so common on Earth. The share of helium and hydrogen on Earth is only about 1%.
The hardest substance in the human body is enamel. It consists mainly of crystalline calcium phosphate (Ca3(POfour)2). On the Mohs scale of hardness, enamel has a hardness of 5 points. The same hardness is possessed by such a mineral as apatite.
Do you think glass is solid or liquid? If we answer that it is liquid, would you be surprised? In fact, glass is an amorphous material that does not have a crystal lattice. Therefore, in a sense, glass molecules behave similarly to liquid molecules. For this reason, glass is constantly flowing. Of course, this current is very slow. For example, if you take glass that was placed in a window frame 20 years ago, then its lower part will be wider than the upper one, as the molecules gradually slide down under the influence of gravity.
Metals shine because they reflect light rays well from their surface, and do not let them through like glass (which makes it transparent), and do not absorb them like soot. At the same time, if we talk about metals, not all of them perfectly reflect sunlight. For example, there are two metals, namely gold and copper, which absorb blue and violet light (short wavelength light) and reflect yellow, orange, and red. Because of this, gold and copper are the only metals that do not have a white or silver tint like other metals.
Both diamond and graphite are made entirely of the same element – pure carbon. However, despite this, they are very different from each other. Diamond is the hardest mineral on the planet, having a 10 out of 10 on the Mohs scale of hardness. Graphite is one of the last in this list (only 2 points).
The rarest element on Earth is astatine. This element is named after the Greek word “ἄστατος”, which translates to “unstable.” Astatine is a naturally occurring semimetal obtained from the decay of uranium and thorium (it is characterized by the properties of non-metals (halogens) and metals (polonium, lead, and others)). In its most stable form, the element has a half-life of only 8.1 hours. As for the natural content in the earth’s crust, according to scientists, its amount does not exceed 28 grams.
The first, almost entirely artificially created chemical element added to the Periodic Table was technetium. It is also the lightest element, composed entirely of unstable radioactive isotopes. The name technetium comes from the Greek word for artificial.
Before 1600, people studied substances to figure out how to turn lead into gold. This was called alchemy. Despite all attempts to turn metals into gold, no one succeeded. As for modern chemistry, it began as a real science in the 1600s. It was then that chemists discovered the simplest substances that make up all other substances. These simple substances are called elements. Chemists have learned that gold and lead are two different elements, so we cannot transform one into the other.
Like physics, biology and a number of other sciences, chemistry has several sections. Here are the five main ones:
- Analytical chemistry. Its essence lies in the development of the theoretical foundations of the chemical analysis of substances and materials.
- Biochemistry. Uses chemical methods to understand how biological systems work at the chemical level.
- Inorganic chemistry. This section studies chemical compounds in inorganic or inanimate objects such as metals and minerals.
- Organic chemistry. This section deals with chemical compounds containing carbon.
- Physical chemistry. This section uses physics concepts to understand how chemistry works.
The most important element for humans and living organisms on Earth is oxygen. And the amazing fact is that as much as 20% of all oxygen present on Earth is produced in the Amazon rainforest. This is the largest rainforest on our planet.
That’s all, dear readers. Thank you for your attention to our website.