Which Of The Following Species Is Diamagnetic

Ever wondered which of the following species is diamagnetic? You might have heard the term tossed around in a chemistry class or seen a diagram of magnetic fields, but the real question is how to spot the one that shows no net magnetic pull. In this post we’ll unpack the idea of diamagnetism, look at a handful of common species, and figure out which one truly has no unpaired electrons pulling it toward a magnetic field.

What Is Diamagnetism?

Diamagnetism is a property found in all materials, but it’s usually so weak that it gets lost amid stronger magnetic effects. Think about it: at its core, diamagnetism means that a species creates a tiny magnetic field in the opposite direction to an applied field. The key to that behavior is electron pairing. When every electron in an atom, ion, or molecule is paired with another electron of opposite spin, the overall magnetic moment cancels out, and the species behaves as diamagnetic.

Electron Pairing and Magnetic Moment

Imagine each electron as a tiny magnet. If two electrons spin in opposite directions, their magnetic fields neutralize each other. So a collection of paired electrons therefore has a net magnetic moment of zero. If even a single electron remains unpaired, the species will show a net magnetic moment and will be attracted to a magnetic field – that’s paramagnetism or ferromagnetism, depending on the context.

Diamagnetism vs. Paramagnetism

Paramagnetic species have one or more unpaired electrons, so they are weakly attracted to a magnetic field. Diamagnetic species, by contrast, have all electrons paired, so they are weakly repelled. The difference is subtle, which is why it’s easy to overlook in everyday observations.

Why It Matters

Understanding which species is diamagnetic isn’t just academic. Practically speaking, in materials science, diamagnetic compounds are used in magnetic levitation and in creating ultra‑stable environments for sensitive experiments. In biology, many biomolecules are diamagnetic, influencing how they interact with magnetic resonance imaging (MRI) fields. Spotting the diamagnetic species among a list helps chemists predict reaction pathways, design catalysts, and even troubleshoot instrumentation.

How to Determine If a Species Is Diamagnetic

The quickest way to answer the question “which of the following species is diamagnetic?” is to examine its electron configuration. Here’s a step‑by‑step approach that works for atoms, ions, and molecules:

Write out the full electron configuration – start from the noble gas core and add the remaining electrons.
Count the unpaired electrons – look at each orbital; if an orbital holds two electrons with opposite spins, they cancel.
Apply the rule – zero unpaired electrons = diamagnetic; any unpaired electron = paramagnetic (or ferromagnetic if the material shows strong ordering).

For molecules, you can use molecular orbital diagrams, but the principle stays the same: paired electrons mean no net magnetic pull.

Common Species and Their Magnetic Behavior

Below we’ll walk through a handful of familiar species and see how the electron‑pairing rule plays out. This should give you a concrete sense of which of the following species is diamagnetic.

Hydrogen Molecule (H₂)

Hydrogen has one electron in its 1s orbital. In H₂, the two hydrogen atoms each contribute one electron, filling the 1s molecular orbital with a pair. No unpaired electrons remain, so H₂ is diamagnetic. In practice, you’ll see it described as “non‑magnetic” in most introductory texts.

Oxygen Molecule (O₂)

Oxygen is a classic example of paramagnetism. Because those electrons aren’t paired, O₂ is attracted to a magnetic field, not repelled. That said, its molecular orbital diagram shows two unpaired electrons in the π* antibonding orbitals. So O₂ would not be the answer to “which of the following species is diamagnetic?

Nitric Oxide (NO)

Nitric oxide has an odd number of electrons, meaning it must have at least one unpaired electron. Its electron configuration leaves a single electron in a π* orbital, making NO paramagnetic. Again, not diamagnetic.

Chlorine Molecule (Cl₂)

Chlorine atoms each bring seven valence electrons. So when they bond, the two 3p orbitals combine to fill the bonding and non‑bonding molecular orbitals, leaving all electrons paired. In real terms, cl₂ therefore has no unpaired electrons and is diamagnetic. If your list includes Cl₂, that’s a strong candidate.

Continue exploring with our guides on sean tried to drink a slushy and how many aces in a pack of cards.

Iron(II) Ion (Fe²⁺)

Transition metals add complexity because d‑orbitals can hold multiple electrons. On top of that, in many coordination environments, the six d‑electrons can pair up, but often there are unpaired electrons depending on the ligand field. Fe²⁺ has a d⁶ configuration. Without a specific context, it’s safer to treat Fe²⁺ as potentially paramagnetic, so it’s not a clear‑cut diamagnetic case.

Water Molecule (H₂O)

Water’s oxygen atom has two lone pairs and two bonding pairs. All electrons are paired, so H₂O is diamagnetic. This is a useful reminder that even small, everyday molecules can display diamagnetism.

Summary of the Example List

If the list you’re looking at contains H₂, O₂, NO, Cl₂, Fe²⁺, and H₂O, the species that are definitely diamagnetic are H₂, Cl₂, and H₂O. Among those, Cl₂ is often highlighted because it’s a diatomic gas that behaves similarly to H₂ but with heavier atoms, making its magnetic behavior a frequent test case. So, if you need to pick a single answer, Cl₂ is a safe bet for “which of the following species is diamagnetic.

What Most People Get Wrong

A common misconception is that all molecules with even numbers of electrons are diamagnetic. That’s not true. Another frequent error is assuming that any molecule that feels “non‑magnetic” in a simple magnet test is automatically diamagnetic. Practically speaking, o₂ has four valence electrons per atom (eight total) but still shows paramagnetism because of the way the electrons occupy molecular orbitals. In reality, the test must be sensitive enough to detect the weak repulsion that characterizes true diamagnetism.

Practical Tips for Identifying Diamagnetism

Start with electron counting – whether you’re dealing with an atom, ion, or molecule, the first step is to tally the electrons.
Use orbital diagrams – for molecules, sketch the molecular orbital energy levels; pair up electrons visually.
Check literature values – many common substances have well‑documented magnetic properties; a quick search can confirm whether a species is known to be diamagnetic.
Beware of temperature effects – some materials become paramagnetic only at elevated temperatures; keep that in mind when interpreting results.

Frequently Asked Questions

Which of the following species is diamagnetic: H₂, O₂, NO, or Cl₂?

Cl₂ is the species that is diamagnetic. Both H₂ and Cl₂ have all electrons paired, while O₂ and NO each possess unpaired electrons.

Can a diamagnetic species become magnetic under any condition?

Yes. If you apply a very strong magnetic field, even a diamagnetic substance will develop a tiny induced magnetic moment opposite to the field. That said, the effect is minuscule and disappears once the field is removed.

Do all molecules with paired electrons show diamagnetism?

Not always. The arrangement of electrons in molecular orbitals matters. Here's one way to look at it: O₂ has paired electrons in bonding orbitals but still has unpaired electrons in antibonding orbitals, making it paramagnetic.

How can I test if a sample is diamagnetic?

A simple pocket magnet won’t detect diamagnetism because the force is weak. Specialized magnetometers or a sensitive torsion balance are needed for a definitive measurement.

Closing Thoughts

Figuring out which of the following species is diamagnetic boils down to a careful look at electron pairing. Whether it’s a simple diatomic like Cl₂, a small molecule such as H₂O, or even a larger compound, the same principle applies. When every electron finds a partner, the species shows no net magnetic pull and behaves as diamagnetic. By counting electrons, sketching orbital diagrams, and consulting reliable data, you can confidently identify the diamagnetic member of any list. Keep this approach in your toolkit, and the next time a question about magnetic behavior pops up, you’ll have a clear, evidence‑based answer ready.