Is It True That Aluminium Is Magnetic?

Under certain conditions, all elements in the periodic table exhibit magnetic. This is owing to the fact that each and every element, under specific conditions, has the power to generate an electric current. Because each element has its own magnetic field, when two magnetic fields come near together, they will respond in a predictable way. Many pupils aren’t aware of the magnetic that exists between aluminium sheets. Let’s see if aluminium magnetic is the answer to the query.

Is aluminium magnetic, then? Yes, aluminium is weakly magnetic in nature because it attracts a magnet weakly when exposed to a magnetic field. Aluminum is not magnetic in the absence of an external magnetic field. The availability of unpaired electrons within the s and p shells of the aluminium atom causes this behaviour.

The attraction or repulsion behaviour is mostly determined by electrons.

A diamagnet is formed when the atoms of an element have paired electrons. The element is paramagnet if it possesses unpaired electrons in its atoms.

Due to the existence of unpaired electrons in both the s and p shells, aluminium is paramagnetic in nature.

Aluminum in an electronic design

Aluminum contains only one electron in the 3p shell, making it an unpaired one, as can be seen in the diagram. The aluminum’s paramagnetism activity is aided by this single unpaired electron.

Why does metal attract a magnet so weakly?

Pairs of electrons spin in opposite directions to cancel out the net dipole moment, as we all know.

The net dipole moment of unpaired electrons does not cancel out during their spin. It turns them into teeny-tiny magnets.

In the presence of an applied external magnetic field, the larger the number of unpaired electrons, the stronger the attraction to a magnet.

In the presence of an external magnetic field, aluminium attracts a magnet weakly because it has just one unpaired electron.

Furthermore, in the absence of an applied external magnetic field, aluminium does not retain any magnetization. Most other paramagnets have this feature as well.

Does the aluminium atom’s s and p shells have a role in its weak magnetism?

Yes. Because of the large overlapping with nearby wave functions, there is usually a strong delocalization in aluminium as a solid.

Aluminum has a large fermi velocity as a result of this, which makes the electrons less sensitive to energy alterations. It results in a lack of magnetism.

Pauli paramagnetism is another name for this phenomenon.

Aluminium’s magnetic susceptibility

Aluminum has a magnetic susceptibility of 2.2m.

m=Km-1 m=Km-1 m=Km-1 m= (x 10-5)

Relative permeability is measured in kilometres.

The element magnetises in the applied external magnetic field when the relative permeability is larger than one.

Furthermore, m stands for magnetic susceptibility, which is not zero if the material responds to any magnetization.

As you can see from the table above, aluminum’s magnetic susceptibility is positive and greater than zero.

It ensures that aluminium attracts to an applied external magnetic field, but the number 2.2 is low, which explains why the attraction is feeble.

NOTE: The range of relative permeability (Km) is 150 to 5000 just for the sake of comparison.

Aluminum’s paramagnetic characteristics

When magnetic susceptibility is larger than zero and lower than zero, the behaviour of paramagnetic and diamagnetic elements is depicted in the diagram.

The aluminum’s paramagnetic activity is depicted in the photographs above.

The first is a graph that shows magnetic susceptibility as a function of temperature. The graph is not linear, indicating that magnetization is inversely proportional to temperature for aluminium.

Does the Curie law apply to aluminium?

Yes. According to Curie’s law, an element’s magnetization is proportional to the applied external magnetic field.

When the element is heated, the degree of proportionality is significantly diminished.

The value eventually settles on a single integer. Magnetization becomes inversely proportional to temperature as a result of this. The metal exhibits an active behaviour as it follows the Curie-Weiss law.

C/(T – ) = m

m = Magnetic susceptibility of molar matter

C stands for Curie constant.

Weiss Constant =

The second image depicts electron mobility in paramagnetic metal.

How can the aluminium be exposed to an external magnetic field?

Simply place the element near a magnet. Let’s look at a few examples to see how this notion works.

If you try to pass a magnet through an aluminium pipe, it will travel slowly and appear to float.

Change the magnet to any other metal and it will pass in a flash. Moving an aluminium can closer to a dangling magnet is another example.

This magnet will begin to move in the same direction as the aluminium. Another example is rolling an aluminium can that has been placed on the floor by bringing and moving a magnet near it.

An electric current is formed by the movement of a magnet within an aluminium pipe and the passage of an aluminium can closer to the magnet.

A magnetic field is formed by this electric current. When the magnetic fields of aluminium and magnet collide, the aluminium attracts the magnet weakly. The phenomena of the Lenz law is causing this.

Also, in the above cases (save for the aluminium pipe), try keeping both the aluminium and the magnet static to see whether any movement occurs. You might not be surprised to see any movement at this point.

For a better understanding, watch the video below.

Some other related questions

What is Pauli paramagnetism, and how does it work?

In comparison to other types of paramagnetism, Pauli paramagnetism is substantially weaker in nature. Because electrons closer to the Fermi surface can change their spin to align with the applied external magnetic field, this is the case.

What is the Fermi surface, and what does it mean?

Only at zero temperature does the surface within reciprocal space separate occupied electrons from unoccupied electron states.

What is Lenz’s law, exactly?

The direction of the electric current induced by changing the magnetic field in a conductor must be such that the magnetic field generated by the electric current opposes the original magnetic field, according to this law.

The dragging behaviour of eddy currents is explained by this law. Aluminum responds to an applied external magnetic field by weakly attracting a magnet within it, according to this rule.

Eddy currents are a type of eddy current.

According to Faraday’s law of induction, an eddy current is a continuous loop of electrical current induced by altering the magnetic field in a conductor.

What is Faraday’s induction law?

It’s an electromagnetic fundamental law that helps anticipate how a magnetic field will react to an induced electric field to produce electromotive force. Electromagnetic induction is another name for this phenomenon.

Is it true that aluminium is a superconductor?

At lower and room temperatures, aluminium is not a superconductor. Aluminum, on the other hand, is a superconductor at high to extremely high temperatures.

Conclusion

Magnetic behaviour exists in all elements, with some exhibiting it even in the absence of an external magnetic field (ferromagnets). Some elements, on the other hand, only exhibit magnetism when an external magnetic field is introduced (paramagnets). Under the influence of an applied external magnetic field, aluminium is one such element that attracts a magnet weakly.

Because aluminium only has one unpaired electron and its spin does not create a strong magnetic behaviour, this attraction is far too feeble. The attraction of paramagnets increases as the number of unpaired electrons increases.

Read more: Is KCl Ionic or Covalent?

Misha Khatri
Misha Khatri is an emeritus professor in the University of Notre Dame's Department of Chemistry and Biochemistry. He graduated from Northern Illinois University with a BSc in Chemistry and Mathematics and a PhD in Physical Analytical Chemistry from the University of Utah.

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