Question

how many moles of boron make up 1.20 × 1024 atoms of boron?

Answer 1

An Avogadro number of atoms of Boron make up 1 mole of Boron atom.

6.02 * 10²³ atoms make up 1 mole of Boron atom.

1.20 * 10²⁴ atoms will:                  (1.20 * 10²⁴ * 1 ) / (6.02 * 10²³)

                                                     ≈1.993 Mole of Boron atom.

Answer 2

Answer: 2 moles

Explanation:

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP and contains avogadro's number $6.023\times 10^{23}$ of particles.

Standard condition of temperature (STP)  is 273 K and atmospheric pressure is 1 atm respectively.

To calculate the moles, we use the equation:

$\text{Number of moles}=\frac{\text{Given atoms}}{\text {Avogadro's number}}=\frac{1.20\times 10^{24}}{6.023\times 10^{23}}=2moles$

Thus 2 moles of boron make up $1.20\times 10^{24}$ atoms of boron.