Answer:
The Avogadro's number is 
Explanation:
From the question we are told that
The edge length is 
The density of the metal is 
The molar mass of Ba is 
Generally the volume of a unit cell is
substituting value
![V = [5.02 *10^{-10}]^3](https://tex.z-dn.net/?f=V%20%3D%20%20%5B5.02%20%2A10%5E%7B-10%7D%5D%5E3)
From the question we are told that 68% of the unit cell is occupied by Ba atoms and that the structure is a metal which implies that the crystalline structure will be (BCC),
The volume of barium atom is
substituting value
The Molar mass of barium is mathematically represented as
Where 
is the Avogadro's number
So
substituting value
The atoms in air are combined with oxygen present in the air and when we inhale the air, oxygen is moved into the body then atoms in oxygen are carried by red blood cells the blood is pumped to the lungs and when oxygen is transported to the body organ, the atoms in lungs become the part of human cells.
Given the data from the question, the mass of arsenic that contains 1.23×10²⁰ atoms is 0.0153 g
<h3>Avogadro's hypothesis </h3>
6.02×10²³ atoms = 1 mole of arsenic
But
1 mole of arsenic = 75 g
Thus, we can say that:
6.02×10²³ atoms = 75 g of arsenic
<h3>How to determine the mass that contains 1.23×10²⁰ atoms</h3>
6.02×10²³ atoms = 75 g of arsenic
Therefore,
1.23×10²⁰ atoms = (1.23×10²⁰ × 75) / 6.02×10²³ atoms)
1.23×10²⁰ atoms = 0.0153 g of arsenic
Thus, 1.23×10²⁰ atoms is present in 0.0153 g of arsenic
Learn more about Avogadro's number:
brainly.com/question/26141731
There are 66 neutrons in a single atom of indium-115. The atomic number of indium-115 is 49, meaning there are 49 protons. Then the atomic mass is 115, so 115-49 = 66.
