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Hebden atomic identity, ions and isotope tables

Use this alongside Hebden atomic identity, ions and isotope tables. Assigned references: p.146 #13–17, p.147 #19, p.149 #22.

p.146 #13–17 · p.147 #19 · p.149 #22

Three counts, three different questions

Atomic number Z is the proton count. For a neutral atom electrons equal Z; an ion’s charge is protons minus electrons. Mass number A is protons plus neutrons. Nuclear charge is +Ze, independent of the electron count.

p.146 · Assigned particle questions

  1. 13a

    For Be, find the number of protons.

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  2. 13b

    For U, find the number of protons.

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  3. 13c

    For Mn, find the number of protons.

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  4. 14a

    For C, find the number of electrons in the neutral atom.

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  5. 14b

    For Fe, find the number of electrons in the neutral atom.

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  6. 14c

    For Ar, find the number of electrons in the neutral atom.

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  7. 15a

    For Na⁺, find the number of electrons in the ion.

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  8. 15b

    For Mg²⁺, find the number of electrons in the ion.

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  9. 15c

    For V³⁺, find the number of electrons in the ion.

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  10. 15d

    For O²⁻, find the number of electrons in the ion.

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  11. 15e

    For Cl⁻, find the number of electrons in the ion.

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  12. 15f

    For Al³⁺, find the number of electrons in the ion.

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  13. 15g

    For Sb³⁻, find the number of electrons in the ion.

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  14. 15h

    For Fe²⁺, find the number of electrons in the ion.

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  15. 15i

    For H⁻, find the number of electrons in the ion.

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  16. 15j

    For As³⁻, find the number of electrons in the ion.

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  17. 17a

    For Mg, enter the positive nuclear charge as a multiple of e (for example, 6 means +6e).

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  18. 17b

    For Ne, enter the positive nuclear charge as a multiple of e (for example, 6 means +6e).

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  19. 17c

    For K⁺, enter the positive nuclear charge as a multiple of e (for example, 6 means +6e).

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  20. 17d

    For S²⁻, enter the positive nuclear charge as a multiple of e (for example, 6 means +6e).

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p.146 · Changing an ion

  1. 16a

    S gains two electrons. Write the new ion.

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  2. 16b

    Ca loses two electrons. Write the new ion.

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  3. 16c

    Cl gains one electron. Write the new ion.

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  4. 16d

    Al loses three electrons. Write the new ion.

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  5. 16e

    Cr³⁺ gains one electron. Write the new ion.

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  6. 16f

    Mn²⁺ loses two electrons. Write the new ion.

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  7. 16g

    V⁴⁺ loses one electron. Write the new ion.

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  8. 16h

    Sb⁻ gains two electrons. Write the new ion.

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  9. 16i

    O²⁻ loses one electron. Write the new ion.

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p.147 · Table

  1. 19

    Complete the isotope/ion table for p.147 #19 on the original.

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p.149 · Table

  1. 22

    Complete the isotope/ion table for p.149 #22 on the original.

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Chemistry student study guide & current class-note scopePrivate class evidence from Mrs. Cote · checked 2026-10-06

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