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Matter and chemistry · Discover & try

What makes one atom a different element?

Reading level 5 of 5 · AdvancedChange
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Atomic identity is determined by nuclear charge, expressed as the proton number. Neutron variation produces isotopes; electron gain or loss produces ions without changing that identity. A probabilistic electron distribution cannot be represented faithfully by little planetary tracks. This schematic therefore uses a cloud-like region and count markers, not a literal electron orbit model.

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atomic number

The number of protons in a nucleus.

isotope

Atoms of one element with different neutron counts.

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See how it works

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Symbolic atom counts and electron cloud, not size, trajectories, nuclear stability or common-ion prediction.

What to look for
  • Protons identify the element
  • Neutrons change the isotope
  • Electrons change net charge
Explain what you noticed

An atom has 6 protons and 6 electrons. Two neutrons are added. What remains unchanged?

Keep this idea: Protons determine the element; neutrons and electrons have different roles.

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Source material checked 2026-10-28. Explanations and activities by Nepedia. Source links do not imply endorsement.

Keep following the idea

How do atoms make different molecules?

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