To determine the mass of 1.00 x 10² platinum (Pt) atoms, we need to first understand how to convert atoms to grams using the molar mass.
The molar mass of platinum is 195.08 g/mol. This value indicates that one mole of platinum atoms (which contains approximately 6.022 x 10²³ atoms, known as Avogadro’s number) has a mass of 195.08 grams.
First, we find the number of moles in 1.00 x 10² atoms:
Number of moles = Number of atoms / Avogadro’s number
Here, substituting the values:
Number of moles = (1.00 x 10² atoms) / (6.022 x 10²³ atoms/mol)
Calculating this gives:
Number of moles ≈ 1.66 x 10⁻² moles
Now, to find the mass of these moles of platinum, we use the molar mass:
Mass = Number of moles x Molar mass
Substituting the values:
Mass = (1.66 x 10⁻²² moles) x (195.08 g/mol)
This calculation yields:
Mass ≈ 3.24 x 10⁻²⁰ grams
So, the mass of 1.00 x 10² platinum atoms is approximately 3.24 x 10⁻²⁰ grams.