if a mole were defined to be 1.00 ×10 ^24 instead of Avogadro s number, what would be the mass of 1 mole of boron atoms?

In present definition, the mass of 6.022 × 10²³ of boron atoms is 10.8 g.

The mass of 1.00 × 10²⁴ boron atoms = (10.8 g) × (1.00 × 10²⁴) / (6.022 × 10²³) = 17.9 g

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In present definition, the mass of 6.02 × 10²³ of boron atoms is 10.8 g.

The mass of 1.00 × 10²⁴ boron atoms = (10.8 g) × (1.00 × 10²⁴) / (6.02 × 10²³) = 18.0 g