Question

Which type of substance is attracted by a magnetic field, a diamagnetic substance or a paramagnetic substance?

Short answer

Paramagnetic substances are attracted by a magnetic field due to the presence of unpaired electrons in their atomic or molecular structure. These unpaired electrons create a magnetic moment that aligns with the external magnetic field, resulting in a net magnetic field in the same direction. In contrast, diamagnetic substances are weakly repelled by a magnetic field.

Step-by-step solution

Definition of Diamagnetic Substances

Diamagnetic substances are materials that have no unpaired electrons in their atomic or molecular structure. When an external magnetic field is applied to a diamagnetic substance, it creates a weak magnetic field that opposes the external magnetic field. As a result, diamagnetic substances are weakly repelled by a magnetic field.

Definition of Paramagnetic Substances

Paramagnetic substances are materials with unpaired electrons in their atomic or molecular structure, which creates a magnetic moment within the atoms or molecules. When an external magnetic field is applied, these magnetic moments align with the external magnetic field, creating a net magnetic field in the same direction as the external magnetic field. Consequently, paramagnetic substances are attracted by a magnetic field.

Determining Which Substance is Attracted by a Magnetic Field

Now that we know the properties of diamagnetic and paramagnetic substances, we can determine which substance is attracted by a magnetic field. Since diamagnetic substances are weakly repelled by a magnetic field and paramagnetic substances align their magnetic moments with the external magnetic field, resulting in a net magnetic field in the same direction, we can conclude that a paramagnetic substance is attracted by a magnetic field.

Key concepts

Diamagnetism

Diamagnetism is a fascinating property of some materials that influence how they interact with magnetic fields. Essentially, diamagnetic substances have no unpaired electrons in their atomic or molecular structure. The electrons in these materials are all paired up, which affects their behavior in the presence of a magnetic field.

• When a magnetic field is applied to a diamagnetic substance, it induces a current that creates its own magnetic field.
• This induced magnetic field is in the opposite direction of the external magnetic field.
• As a result, this opposition causes the diamagnetic substance to be weakly repelled by the magnetic field.

This means that diamagnetic materials do not have a net magnetic moment, so they cannot be attracted to magnets like paramagnetic materials. Common examples of diamagnetic substances include bismuth, copper, and water. Diamagnetism is a universal property of materials, but in most substances, it is very weak compared to other types of magnetism like paramagnetism or ferromagnetism.

Magnetic fields

Magnetic fields are invisible forces that have a significant influence on magnetic materials and are a key aspect of understanding magnetism as a whole. A magnetic field is generated by moving electrical charges and can exert forces on other charges that are moving. These fields are characterized by their strength and direction and are essential in various technological applications such as motors, magnetic storage devices, and MRI machines.

• Magnetic fields can be visualized as lines of force emanating from a magnet, going from its north pole to its south pole.
• They can penetrate and influence nearby materials without making physical contact.

Magnetic fields interact differently with various substances:

• Diamagnetic materials create an opposing field and are repelled by magnetic fields.
• Paramagnetic materials, with unpaired electrons, align with the magnetic field and are attracted to it.

Understanding how materials react to magnetic fields helps in distinguishing different types of materials based on their magnetic properties.

Unpaired electrons

The presence of unpaired electrons in atoms or molecules plays a crucial role in determining the magnetic properties of a substance. Unpaired electrons have a magnetic spin, which creates a small magnetic moment, making the substance magnetically responsive in different ways.

• In paramagnetic substances, the unpaired electrons have magnetic moments that can align with an external magnetic field.
• This alignment enhances the overall magnetic field within the substance and leads to an attraction to the magnetic field.

Conversely, diamagnetic substances have all their electrons paired up, which leads to no net magnetic moment. As a result, there is no natural alignment with the magnetic field, and these substances react by opposing the magnetic field slightly.

• Unpaired electrons are vital in applications such as MRI (Magnetic Resonance Imaging), where the magnetic properties of atoms in the human body are exploited for diagnostic purposes.

Understanding the role of unpaired electrons provides insight into why certain materials are attracted to or repelled by magnetic fields and can be used to predict the behavior of the material in a magnetic context.