科学の学習ルート

From one atom to the periodic table

Carbon-12 has 6 protons and 6 neutrons; changing the proton count would create a different element.

ここから始める

Carbon-12 has 6 protons and 6 neutrons; changing the proton count would create a different element.

考えをつなぐ

1

Carbon-12 has 6 protons and 6 neutrons; changing the proton count would create a different element.

2

Sodium has 11 electrons; its outer 3s electron helps explain why sodium readily forms Na+.

3

Across period 3, atomic size generally falls while first ionization energy generally rises, with instructive exceptions.

具体的な確認点

The periodic table is a map of repeating electron structures. Moving across a row changes nuclear charge and electron arrangement together, producing trends—and useful exceptions.

さらに深く

Atomic Structure · Electron Configuration · Periodic Trends

参考資料

IUPAC · CIAAW 2024 · NIST · BIPM SI Brochure