<span>Avogadro's number
represents the number of units in one mole of any substance. This has the value
of 6.022 x 10^23 units / mole. This number can be used to convert the number of
atoms or molecules into number of moles. We calculate as follows:
2.30 g NH3 (1 mol / 17.03 g ) (</span>6.022 x 10^23 molecules / 1 mol ) = 8.13x10^22 molecules
To calculate the number of moles, simply take the ratio of mass and molar mass. The molar mass of Iron (Fe) is equal to 55.85 g/mol.Therefore the total number of moles is:
moles Fe = 25.7 g / (55.85 g / mol)
moles Fe = 0.46 mole
Your answer is a, boron. Boron has 5 protons, 6 neutrons, and 5 electrons. Hope this helps!
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