How many Si atoms in 12.5 g sample of silicon?

Answer 1

Silicon is a common metalloid which is a chemical element but it is considered to be tetravalent metalloid which has only 4 available electrons for covalent chemical bonding in its valence region. In the Periodic Table, Silicon has atomic number 14 with Si symbol. It is good to know that silicon is less reactive that Carbon-14 based on its position in the periodic table which is in the bottom of Carbon.

The Standard Atomic Weight for Silicon is 28.0855 grams. The standard is based on the Avogadro's Constant which is 6.02214179 x 1023 mol-1. 1 mol of silicon will contains 6.02214179 x 1023 atoms of silicon. So, how many atoms are present in 12.5 gram of silicon?

In 1 mol silicon (28.0855 grams) = 28.0855/28.0855 x 6.02214179 x 1023 = 6.02214179 x 1023 atoms

In 12.5 gram silicon = 12.5/28.0855 x 6.02214179 x 1023 = 2.680271755 x 1023 atoms

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