Answer:
8.5 × 10²² atom / cm³, 2.125 × 10²² unit cells / cm³, 4.7 × 10⁻²³ cm³ / cell unit, 3.61 × 10⁻⁸ cm /cell
Explanation:
The density of the solid Cu = 8.96 g/cm³
a) number of atoms present
mole = mass / molar mass = (8.96 g/cm³) / 63.546 = 0.141 mol
number of atoms = mole × avogadro's constant = 0.141 × 6.02 × 10²³ = 8.5 × 10²² atom / cm³
b) a face-centered cubic unit cell contains 4 atoms
8.5 × 10²² atom / cm³ / 4 = 2.125 × 10²² unit cells / cm³
c) the volume of a unit cell of the metal = reciprocal of 2.125 × 10²² unit cells / cm³ = 1 ÷ ( 2.125 × 10²² unit cells / cm³ ) = 4.7 × 10⁻²³ cm³ / cell unit
the edge length of a cell of cu = ∛(4.7 × 10⁻²³ cm³ / cell unit) = 3.61 × 10⁻⁸ cm /cell
Answer:
Earth, Venus, mars, Mercury , Neptune, Saturn, Jupiter , Uranus
Explanation:
The Ancient Egyptians used simple sundials and divided days into smaller parts, and it has been suggested that as early as 1,500BC, they divided the interval between sunrise and sunset into 12 parts. ... Known as a clepsydra, it uses a flow of water to measure time.
