Answer:
30.11 × 10¹⁷ atoms
Step-by-step explanation:
Given data:
Mass of Au = 1 mg (0.001 g)
Number of molecules / atom = ?
Solution:
The given problem will solve by using Avogadro number.
It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.
The number 6.022 × 10²³ is called Avogadro number.
For example,
Number of moles of Au = mass/ molar mass
Number of moles of Au = 0.001 g/ 197 g/mol
Number of moles of Au = 5 × 10⁻⁶ mol
Number of atoms:
one mole = 6.022 × 10²³ atoms
5 × 10⁻⁶ mol × 6.022 × 10²³ atoms / 1mol
30.11 × 10¹⁷ atoms