Questions tagged [periodic-trends]
Trends which are observed in the properties of elements as you move along the periodic table in a given direction.
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Why are there two Hydrogen atoms on some periodic tables?
Most periodic tables only feature one Hydrogen atom, on the top of the first group. But some, like the one I was given, also show Hydrogen in the 7th group, to left of Helium.
Why are there two ...
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Are there any major exceptions when comparing electron affinity?
I was tasked with figuring out whether carbon or nitrogen has a more negative electron affinity value. I initially picked nitrogen, just because nitrogen has a higher $Z_\mathrm{eff}$, creating a ...
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Why do atoms generally become smaller as one moves left to right across a period?
It seems to me that the addition of electrons and protons as you move across a period would cause an atom to become larger. However, I'm told it gets smaller. Why is this?
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