Answer: The number of atoms found in given amount of magnesium is

Step-by-step explanation:
To calculate the number of moles, we use the equation:

Given mass of magnesium = 4.20 g
Molar mass of magnesium = 24.31 g/mol
Putting values in above equation, we get:

According to mole concept:
1 mole of an element contains
number of atoms
So, 0.173 moles of an element contains =
number of atoms
Hence, the number of atoms found in given amount of magnesium is
