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boron

Which atomic number belongs to boron on the periodic table?

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A labeled diagram of the periodic table entry for boron shows its atomic number 5, symbol B, electron configuration, atomic weight range, and classification as a solid, weakly acidic, other nonmetal with a rhombohedral crystal structure at room temperature. — boron Properties of boron.

The atomic number of boron is 5. This places it in Group 13 of the periodic table, where it is classified as a semimetal.1