Answer: 1.505 * 10^24 atoms
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Work Shown:
1 mole = 6.02 * 10^23 atoms
2.5*(1 mole) = 2.5*(6.02 * 10^23 atoms)
2.5 moles = (2.5*6.02) * 10^23 atoms
2.5 moles = (15.05) * 10^23 atoms
2.5 moles = (1.505 * 10^1) * 10^23 atoms
2.5 moles = 1.505 * (10^1*10^23) atoms
2.5 moles = 1.505 * 10^(1+23) atoms
2.5 moles = 1.505 * 10^24 atoms
This is true for any element. This value is an approximation since there are roughly 6.02 * 10^23 atoms in 1 mole of any element.
