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Ions: 4s electrons are lost first

When a first-series atom is oxidized it loses its 4s electrons first, then 3d electrons one by one for higher states.

The idea, in English

When a first-series atom is oxidized it loses its 4s electrons first, then 3d electrons one by one for higher states. All members except Sc show +2 (book: after losing the 4s electrons; for Cr and Cu, which have 4s1, the second electron comes from 3d).

Examples

Fe2+ [Ar]3d6, Fe3+ [Ar]3d5, Cr2+ [Ar]3d4, Cu2+ [Ar]3d9, Zn2+ [Ar]3d10.

Explain in Egyptian Arabic

لما ذرة من الـ first-series تتأكسد، بتفقد الـ 4s electrons الأول، وبعدين الـ 3d electrons واحد ورا التاني عشان توصل لـ states أعلى. كل العناصر ما عدا الـ Sc بتدّي +2 (الكتاب بيقول: بعد ما تفقد الـ 4s electrons؛ وفي الـ Cr والـ Cu، اللي عندهم 4s1، الـ electron التاني بييجي من الـ 3d).

أمثلة

Fe2+ [Ar]3d6، Fe3+ [Ar]3d5، Cr2+ [Ar]3d4، Cu2+ [Ar]3d9، Zn2+ [Ar]3d10.

المطلوب

تكتب configuration أي ion، وتعرف العنصر من configuration الـ ion بتاعه.

Common misconceptions

  • The last electron added leaves first, so Fe2+ = [Ar] 4s2 3d4.

    4s leaves first: Fe2+ = [Ar] 3d6.

    Explain in Egyptian Arabic

    لأ، الـ 4s هو اللي بيطلع الأول، مش آخر electron دخل: Fe2+ = [Ar] 3d6.

  • Cr2+/Cu2+ keep the 4s1 anomaly.

    Ions are built by removing 4s first.

    Explain in Egyptian Arabic

    مش صح، الـ ions بتتبني بإننا نشيل الـ 4s الأول، فالـ 4s1 بيروح هو كمان.

  • Every element of the series has a +2 state.

    Not every element

    scandium shows +3 in the book table, not +2. The other members show +2 after losing their 4s electrons (for Cr and Cu, which have 4s¹, the second electron comes from 3d).

    Explain in Egyptian Arabic

    لأ، الـ Sc مالوش غير +3.

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