Any child knows that metals are attracted to magnets. After all, they repeatedly hung magnets on the metal door of the refrigerator or letters with magnets on a special board. However, if you attach a spoon to the magnet, there will be no attraction. But the spoon is also metal, why then happens? So, let's find out which metals are not magnetized.
Scientific point of view
To determine which metals are not magnetized, you need to find out how all metals can relate to magnets and the magnetic field. With respect to the introduced magnetic field, all substances are divided into diamagnets, paramagnets and ferromagnets.
Each atom consists of a positively charged nucleus and negatively charged electrons. They move continuously, which creates a magnetic field. The magnetic fields of the electrons of one atom can amplify each other or destroy, which depends on the direction of their movement. And can be compensated:
- The magnetic moments caused by the movement of electrons relative to the nucleus are orbital.
- The magnetic moments caused by the rotation of electrons around its axis are spin ones.
If all magnetic moments are equal to zero, the substance is referred to as diamagnetics. If only spin moments are compensated, to paramagnets. If the fields are not compensated - to ferromagnets.
Paramagnets and ferromagnets
Consider the option when each atom of matter has its own magnetic field. These fields are multidirectional and cancel each other out. If a magnet is placed next to such a substance, then the fields will orient in one direction. A substance will have a magnetic field, a positive and a negative pole. Then the substance will be attracted to the magnet and can itself be magnetized, that is, it will attract other metal objects. So, for example, you can magnetize steel clips at home. Each will have a negative and positive pole and it will even be possible to hang a whole chain of paper clips on a magnet. Such substances are called paramagnetic.
Ferromagnets are a small group of substances that are attracted to magnets and easily magnetized even in a weak field.
Diamagnetics
In diamagnets, the magnetic fields inside each atom are compensated. In this case, when a substance is introduced into a magnetic field, the motion of electrons under the influence of the field will be added to the proper motion of the electrons. This movement of electrons will cause an additional current, the magnetic field of which will be directed against the external field. Therefore, the diamagnet will weakly repel from a nearby magnet.
So, if you approach the question from a scientific point of view, which metals are not magnetized, the answer will be - diamagnetic.
Distribution of paramagnets and diamagnetics in the periodic system of periodic elements
The magnetic properties of simple substances periodically change with increasing serial number of the element.
Substances that are not attracted to magnets (diamagnets) are located mainly in short periods - 1, 2, 3. What metals are not magnetized? These are lithium and beryllium, and sodium, magnesium and aluminum are already referred to as paramagnets.
Substances attracted to magnets (paramagnets) are located mainly in long periods of the periodic system of Mendeleev - 4, 5, 6, 7.
However, the last 8 elements in each long period are also diamagnets.
In addition, three elements are distinguished - carbon, oxygen and tin, the magnetic properties of which are different for different allotropic modifications.
In addition, another 25 chemical elements are named whose magnetic properties could not be established due to their radioactivity and rapid decay or complexity of synthesis.
The magnetic properties of lanthanides and actinides (all of them are metals) vary irregularly. Among them are para- and diamagnetics.
Special magnetically ordered substances are isolated - chromium, manganese, iron, cobalt, nickel, whose properties change irregularly.
What metals are not magnetized: list
There are only 9 ferromagnets, that is, metals that are well magnetized in nature. These are iron, cobalt, nickel, their alloys and compounds, as well as six lanthanide metals: gadolinium, terbium, dysprosium, holmium, erbium and thulium.
Metals that are attracted only to very strong magnets (paramagnets): aluminum, copper, platinum, uranium.
Since in everyday life there are no such large magnets that would attract a paramagnet, and also no lanthanide metals, it can be safely stated that all metals except iron, cobalt, nickel and their alloys will not be attracted to magnets.
So, which metals do not magnetize to a magnet:
- paramagnets: aluminum, platinum, chromium, magnesium, tungsten;
- diamagnets: copper, gold, silver, zinc, mercury, cadmium, zirconium.
In general, we can say that ferrous metals are attracted to the magnet, non-ferrous metals are not attracted.
If we talk about alloys, then iron alloys are magnetized. These include primarily steel and cast iron. Precious coins can also be attracted to the magnet, since they are made not of pure non-ferrous metal, but of an alloy that may contain a small amount of a ferromagnet. But jewelry made of pure non-ferrous metal will not be attracted to the magnet.
What metals do not rust and magnet? This is a common food stainless steel, gold and silver products.