Determine valence electrons using the periodic table (article) | Khan Academy (2024)

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• Steve

  6 months agoPosted 6 months ago. Direct link to Steve's post “Why doesn't helium have 8...”

  Why doesn't helium have 8 electrons instead of 2?

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  (4 votes)

  • vincent.wang11

    6 months agoPosted 6 months ago. Direct link to vincent.wang11's post “Since helium is the secon...”

    

    Since helium is the second element in the table, a neutral helium atom can't have 8 electrons as it only has two. The other elements have an atomic number greater than 8.

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    (22 votes)
• Susan Everly

  3 months agoPosted 3 months ago. Direct link to Susan Everly's post “so how many valence elect...”

  so how many valence electrons does group 3-12 have? or do they have none at all?

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  (5 votes)

  • Infrared

    3 months agoPosted 3 months ago. Direct link to Infrared's post “It varies. Also, they hav...”

    It varies. Also, they have a weird habit of being able to have more than one oxidation state. Iron (26) is in the 8th group and usually has a charge of +2 or +3.

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    (7 votes)

    See Also

    2.9: Valence ElectronsWhat Are Valence Electrons? Definition and Periodic Table
• kristine.aboloje

  6 months agoPosted 6 months ago. Direct link to kristine.aboloje's post “How many electrons can fi...”

  How many electrons can fill each shell?

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  (2 votes)

  • Anushka

    4 months agoPosted 4 months ago. Direct link to Anushka's post “first shell is 2, second ...”

    first shell is 2, second shell is 8, third shell is 18, and then 32.

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    (4 votes)
• alexa araujo

  5 months agoPosted 5 months ago. Direct link to alexa araujo's post “How many electrons can fi...”

  How many electrons can fill each shell?

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  (2 votes)

  • Pierce, Greyson

    5 months agoPosted 5 months ago. Direct link to Pierce, Greyson's post “2, 8, 18, 32, 32, 18, 2. ...”

    2, 8, 18, 32, 32, 18, 2. IT follows the rule of 2n^2, where n is equal to the position of the shell.

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    (3 votes)
• Squirrel

  5 months agoPosted 5 months ago. Direct link to Squirrel's post “What about the elements a...”

  What about the elements at the bottom who can't really fit in so they left it out? How much valence electrons do they have?

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  (1 vote)

  • Infrared

    3 months agoPosted 3 months ago. Direct link to Infrared's post “They have three to four v...”

    They have three to four valence electrons, according to my research.

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    (2 votes)
• Joselin Cornu ventura

  9 days agoPosted 9 days ago. Direct link to Joselin Cornu ventura's post “who invented the periodic...”

  who invented the periodic tablet

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  (0 votes)

  • trini

    9 days agoPosted 9 days ago. Direct link to trini's post “Dmitri Mendeleev made the...”

    Dmitri Mendeleev made the design of the modern periodic table we know of today, but Alexandre-Emile Beguyer de Chancourtois organized the elements by atomic "weight" 5 years earlier.

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    (3 votes)
• Kytzia

  24 days agoPosted 24 days ago. Direct link to Kytzia's post “how can you remember the ...”

  how can you remember the names of the period table

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  (1 vote)

  • piggy✩°｡⋆

    23 days agoPosted 23 days ago. Direct link to piggy✩°｡⋆'s post “i memorise it usinghttps...”

    i memorise it using
    https://www.youtube.com/watch?v=rz4Dd1I_fX0
    its helpful.

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    (1 vote)
• CatGutz

  2 months agoPosted 2 months ago. Direct link to CatGutz's post “Are the electrons always ...”

  Are the electrons always in the same spot in the rows or can it be different?

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  (1 vote)
• Ali ZainB

  21 days agoPosted 21 days ago. Direct link to Ali ZainB's post “why is helium grouped wit...”

  why is helium grouped with the other elements in group 18 if it only has 2 valence electrons? Doesn't it make the table more confusing?

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  (1 vote)

  • overworked

    16 days agoPosted 16 days ago. Direct link to overworked's post “It is because the first s...”

    It is because the first shell can have a maximum of 2 electrons. All the elements in group 18 have like a perfect full number of electrons supported in their energy level. Making all those elements also non reactive as they are not missing a valence electron. I hope what i said was understandable!!

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    (1 vote)
• davidcsjohnson

  a month agoPosted a month ago. Direct link to davidcsjohnson's post “Why is He in group 18 and...”

  Why is He in group 18 and not group 2? Wouldn't it make more sense to put it in group 2 so the number of VE is the same as the others in the group since that seems to be the way it is organized?

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  (1 vote)

  • 🌊 ~Saanvika~ 💙

    10 days agoPosted 10 days ago. Direct link to 🌊 ~Saanvika~ 💙's post “That is because helium ha...”

    That is because helium has a full outer shell like the noble gases it is grouped with, and shares many other properties with the noble gases in group 18. Hope this helps!

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    (1 vote)