Answer:
Electron cloud
Explanation:
The electron cloud is an informal term in chemistry and physics. This region describes the negatively charged electrons in their orbit surrounding the nucleus in an atom. The nucleus has protons in it that have a positive charge on it. It is not easy to know where exactly an electron in any specific time but the electron cloud helps to know electron is moving in this specific area.
Answer:
Percentage abundance of 121 Sb is = 57.2 %
Percentage abundance of 123 Sb is = 42.8 %
Explanation:
The formula for the calculation of the average atomic mass is:
Given that:
Since the element has only 2 isotopes, so the let the percentage of first be x and the second is 100 -x.
For first isotope, 121 Sb :
% = x %
Mass = 120.9038 u
For second isotope, 123 Sb:
% = 100 - x
Mass = 122.9042 u
Given, Average Mass = 121.7601 u
Thus,

Solving for x, we get that:
x = 57.2 %
<u>Thus, percentage abundance of 121 Sb is = 57.2 %
</u>
<u>percentage abundance of 123 Sb is = 100 - 57.2 % = 42.8 %</u>
The Answer you're looking for here is Star A mainly because it's the star with the highest Surface Temperature on the Graph.