How many grams do 5.2×10^20 atoms of silicon weigh?
Answer in units of g.
5.2E20 atoms x (1 mole/6.022E23) = ??moles Si.
1 mole Si has a mass of 28.1 g; therefore, ??mols will have a mass of______g?
.02
0.024g
To find the weight in grams, you need to employ the concept of molar mass.
1. Determine the molar mass of silicon:
The molar mass of silicon is found on the periodic table, and it is approximately 28.09 grams per mole (g/mol).
2. Calculate the number of moles:
To do this, divide the number of atoms by Avogadro's number, which is approximately 6.022 x 10^23 atoms/mol.
5.2 x 10^20 atoms ÷ (6.022 x 10^23 atoms/mol)
3. Multiply the number of moles by the molar mass:
This calculation will give you the weight of silicon in grams.
(number of moles) x (molar mass) = (weight in grams)
Let's perform the calculations:
5.2 x 10^20 atoms ÷ (6.022 x 10^23 atoms/mol) ≈ 0.000086 mol
0.000086 mol x 28.09 g/mol ≈ 0.00242 grams (rounded to 5 decimal places)
Therefore, 5.2 x 10^20 atoms of silicon weigh approximately 0.00242 grams.