Answer:- The natural abundance of 
is 0.478 or 47.8% and 
is 0.522 or 52.2% .
Solution:- Average atomic mass of an element is calculated from the atomic masses of it's isotopes and their abundances using the formula:
Average atomic mass = mass of first isotope(abundance) + mass of second isotope(abundance)
We have been given with atomic masses for and as 150.919860 and 152.921243 amu, respectively. Average atomic mass of Eu is 151.964 amu.
Sum of natural abundances of isotopes of an element is always 1. If we assume the abundance of as n then the abundance of would be 1-n .
Let's plug in the values in the formula:
151.964=150.919860n+152.921243-152.921243n
on keeping similar terms on same side:
negative sign is on both sides so it is canceled:
The abundance of is 0.478 which is 47.8%.
The abundance of is = 
= 0.522 which is 52.2%
Hence, the natural abundance of is 0.478 or 47.8% and is 0.522 or 52.2% .
Answer:
Identical
Explanation:
Both compounds are identical. If you rotate the compound on the left 60 degree anticlockwise you will get the compound on the right.
These are not isomers of each other because they have same structural and molecular formulas.
Also, they are related to each other because they are the same
Answer:
C
Explanation:
For sodium to bond with chlorine, it is through electrovalent bonding.
It means , one electron is transferred from the sodium to the chlorine.
Normally, chlorine has 17 electrons, by adding one , we get 18 electrons.
This is the number of electrons for Argon
Think it is b
but i am not sure at all
Liquids are similar to gases in that they both have <span>no definite shape.</span>
