Answer:
68.77×10²³ atoms
Explanation:
Given data:
Density of Al = 2.70 g/cm³
Volume of Al block = 114.2 cm³
Number of atoms of Al = ?
Solution:
First of all we will determine the mass of Al.
D = m/v
2.70 g/cm³ = m/114.2 cm³
m = 2.70 g/cm³ × 114.2 cm³
m = 308.34 g
Now we will calculate the number of moles of Al.
Number of moles = mass/molar mass
Number of moles = 308.34 g/27 g/mol
Number of moles = 11.42 mol
Number of atoms of Al:
1 mole = 6.022×10²³ atoms
11.42 mol × 6.022×10²³ atoms/1 mol
68.77×10²³ atoms
