Which is bigger: sodium or chlorine?
Sodium and chlorine sit next door in the same period, but one is much larger. Decide which, then test the down-a-group trend.
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1 lesson for “Periodic table trends”
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Why does sulfur have 6 valence electrons, not 16?
Sulfur has 16 total electrons but only 6 that do chemistry. Learn where those 6 live and how the periodic table reveals them.
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