Step 1: Calculate the mass of silicon in 1cm3.
The density of silicon is given as 2.23 cm3g.
Mass = Density × Volume
Mass=2.23 cm3g×1cm3=2.23g
Step 2: Calculate the number of moles of silicon in 1cm3.
The atomic mass of silicon is 28.09 molg.
Number of moles = AtomicMassMass
Numberofmoles=28.09 molg2.23g≈0.07938mol
Step 3: Calculate the number of atoms in 1cm3 of silicon.
Use Avogadro's number, which is 6.022×1023 molatoms.
Number of atoms = Number of moles × Avogadro's number
Numberofatoms=0.07938mol×6.022×1023 molatoms
Numberofatoms≈4.781×1022atoms
The number of atoms in 1cm3 of silicon is:
4.781×1022atoms
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