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Find the Noble Gas

Chemistry Level 1

The following are electron configurations of neutral atoms. Which one represents a noble gas?

\[\ 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2 3d^8\] \[\ 1s^2 2s^2 2p^6 3s^1\] \[\ 1s^2 2s^2 2p^6 3s^2 3p^6\] \[\ 1s^2 2s^2 2p^5\]

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by Jordan Calmes

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