What is the metal that melts in the palm of your hand?

<> November 6, 1875, the French chemist Boisbeaudrand presented the first precious milligram of gallium metal to the French Academy of Sciences. Now, let's find out what kind of thing gallium is!

Have you ever seen such a wonderful metal? At room temperature, it is a piece of silvery metal; If you want to take a closer look at it, put it in the palm of your hand and look at it, hey, it will melt in no time, flowing around in the palm of your hand like droplets of water rolling on a lotus leaf.

What kind of wonderful metal is this? Its name is gallium. Gallium was discovered in 1875 by the French chemist Boisbeaudrand.

In honor of his homeland, Boisbodran named it "gallium", which is the ancient French name "home". The melting point of gallium is only, and the human body temperature is 37, put gallium in the palm of your hand, and naturally melt quickly.

Gallium has a strange temper: its melting point is low, but its boiling point is so high that it doesn't boil until 1893! That is, from 1893 onwards, gallium was always in liquid form, while mercury boiled at 360.

So, gallium is used to make high-temperature thermometers. The casing of this thermometer is made of quartz glass that is resistant to high temperatures. It can measure high temperatures below 1500.

Gallium is soft and can be cut into pieces with a knife.

Gallium goes well with glass. Gallium plating on glass makes a great mirror. Due to its ability to reflect light and withstand high temperatures, gallium mirrors have been used in a variety of special industrial applications.

Gallium has a low melting point and can be made into fusible alloys with zinc, tin, indium, etc., which are used to make automatic fire-fighting faucets - when there is a fire, as soon as the temperature rises, the fusible alloy melts, and water is automatically sprayed out of the faucet. Adding a small amount of gallium to magnesium can improve the corrosion resistance of magnesium. Gallium is also used to make dental alloys.

In the nuclear industry, the alloy of gallium and thallium is used as a heat carrier.

Gallium is very rare on Earth, so it is rarely seen in daily life. Gallium usually lives in ores such as vanadium earth ore, sphalerite, etc.

In addition to gallium, cesium also melts immediately when placed on the hand. The melting point of cesium is lower than that of gallium, which is only 28. Cesium, like gallium, is also a rare metal.

Cesium was discovered in 1860 by the German chemist Bunsen using spectroscopic analysis. Cesium is a silvery-white metal that is chemically very reactive. In the air, it spontaneously combusts, emitting a purple glow.

When cesium is exposed to light, it releases electrons. People take advantage of this characteristic of cesium and use it to make photocells. The stronger the light, the greater the photocurrent, which becomes an important component in the automatic control equipment.

In addition, photocells are also used in movies, television, and photometers. In medicine, the compound of cesium is used to treat shock, diphtheria, etc.

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Collapse. The world's most "special" metal can melt in the hand, what is the principle?

The world's most "special" metal can melt in the hand, what is the principle?

Gallium. 1. Gallium was discovered in Paris in 1875 by Bois. He observed a new purple line on the atomic spectrum of zinc extracted from sphalerite ore (ZNS). He knew it meant that an unknown element had appeared.

2. What Boisbodrand did not realize was that its existence and properties had been successfully predicted by Mendeleev, whose periodic table showed that there was a gap under the aluminum that had not yet been occupied. The atomic weight of this unknown element is about 68, and its density.

3. In November 1875, Bois Baudrand extracted and purified this new metal and proved that it resembled aluminum. In December 1875, he announced it to the French Academy of Sciences.

Gallium metal is a very soft metal, and it is non-toxic to people, and body temperature can make it melt, so it has attracted the attention of many test brothers, but compared to other metals, the form of this substance is too easy to change.

A piece of silvery-white metal is placed in the palm of your hand, and when you just want to look at it carefully, it melts and flows like mercury, and you have to hold it carefully as if it were a large droplet. It's gallium metal.

When the French chemist Boisbordran discovered it in 1875, in honor of his homeland, he named it after the ancient French name - Gaia, referred to as gallium. The melting point of gallium is only, lower than the body temperature of a person, so it will melt in the palm of the hand; However, gallium has a boiling point of 2403, which is used to make high-temperature thermometers. Because the boiling point of mercury is 357, the mercury thermometer is generally 350, of course, there are more than 400, but it is easy to produce bubbles due to heat, affecting the accuracy, and the gallium thermometer made of quartz tube can measure the high temperature of 1500, which can be called the champion of direct reading thermometers.

Due to the low melting point of gallium, it can be made of fusible alloy, which is used as a plug on the fire hydrant, once the temperature rises, the plug melts, and the water can automatically spray out to extinguish the fire, and the firefighters can quickly find it, and the fire hydrant mouth is also protected by the cooling of water and will not be burned.

Cesium, which was discovered 15 years later than gallium, has a lower melting point than gallium, only; But no one dares to put it in the palm of the hand, because it is too lively, it will spontaneously combust in the air, and it can ** in the water, if it is placed in the palm of the hand, it will not burn the skin of the flesh? People can only put it in kerosene, and it is as old as celery.

Kerosene loves fire so much, isn't it dangerous? No, because kerosene isolates air and water, cesium will not burn, let alone **.

Because cesium reacts violently with water, it has been used as a desiccant in electron tubes. A very small amount of cesium absorbs a trace amount of water vapor in the vacuum tube, which can greatly improve the vacuum degree and prolong the life of the tube. When light shines on the metal cesium, it can release a beam of electrons, and scientists use this property of cesium to make a photocell.

A photocell is a device that when exposed to light, it has an electric current passing through it, and this electrical signal can be used for automatic control. When you approach the door of the Beijing Hotel, the door opens automatically, and when you enter, the door closes automatically, which is the photocell directing the opening and closing of the automatic door.

In recent years, cesium has taken on a new role as a time measurement standard, called "cesium atomic beam time frequency reference device". This is currently the most accurate and stable time-frequency measurement benchmark in the world, accurate to 10 parts per trillion, 300,000 years is less than 1 second. This is indispensable for astronomical measurements and space flight, where time is often measured in microseconds (1 millionth of a second).

Yes. Gallium [jiā ].

Gallium is one of the rarest metals on Earth. It is only found in zinc compounds in bauxite ores, and the metal has a unique property - it has a melting point of degrees Celsius. Gallium metal, if exposed to ** for a long time, may cause acute poisoning and death from hunger.

Symptoms include transient excitability, lethargy, uncoordinated movements, fatigue, reflexes, changes in respiratory rate, and uncoordinated movement of the lower extremities. Because gallium melts easily, transporting it requires a special polyethylene-wrapped companion modification.

Because the electrons of the metal tend to detach, it has good electrical conductivity, and the metal element is usually valentinized in the compound, but when the temperature is higher, it is affected by the nucleus.

The resistance will become larger. The link between the metal molecules is the metallic bond.

Therefore, the connection can be re-established by changing positions at will, which is also the reason for the good stretchability of the metal.

In nature, the vast majority of golden-naqing exists in a chemical state, and a few metals such as gold, silver, platinum, and bismuth exist in a free state.

Exist. Most of the metal minerals are oxides and sulfides, and other forms are chlorides, sulfates, carbonates and silicates.

Substances that belong to metals are gold, silver, copper, iron, manganese, zinc, etc. at a pressure of one atmosphere and 25 degrees Celsius.

At room temperature, all metals are solid except mercury (liquid). Most of the pure metals are silvery-white (gray) color, and only a few are not, such as gold is yellow-red, and copper is purple-red. Most of the metals are next to the "Iron".

It will usually have a positive temperature resistivity.

A substance is defined as a metal. Use 112

Metals are in the periodic table.

Metals are in the periodic table.

In the periodic table of various elements, there are 90 types of metal elements. Located at the bottom left of the "boron-astatine dividing line", there are metal elements and transition elements in five areas, including S, P, D, and F.

It's all metallic elements.

Within a solid metal conductor, there are a lot of free electrons that can be moved. Although these electrons are not bound to any particular atom, they are bound to the crystal lattice of the metal; Even in the absence of an external electric field, these electrons move randomly due to heat. However, within the conductor, the average net current is zero.

The number of electrons moving from one side of the section to the other at any time interval is equal to the number of electrons moving through the section in the opposite direction.