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: 1800 L
Explanation:
Given that,
Original pressure of gas (P1) = 180 kPa
Original volume of gas (V1) = 1500 L
New pressure of gas (P2) = 150 kPa
New volume of gas (V2) = ?
Since pressure and volume are given while temperature is held constant, apply the formula for Boyle's law
P1V1 = P1V2
180 kPa x 1500 L = 150 kPa x V2
270000 kPa•L = 150 kPa•V2
Divide both sides by 150 kPa
270000 kPa•L/150 kPa = 150 kPa•V2/150 kPa
1800L = V2
Thus, the new volume of the gas is 1800 liters.
Answer: Raw data, perhaps.
Explanation: I'm not certain what the question is seeking for an answer, but I would suggest "raw data" would be a reasonable choice. It reflects the data was recorded, but not yet processed to provide a conclusion or observation.
If one were a bit snarky, other possiblities include
- a pile of dung
- my labmate's scrawls, or
- the best web results I could find
Answer:
no se pero gana pls PorFAVORRRRRR.... DOXEADO TU IP 19503236
<span>A melting point is the characteristic physical property of a substance. So melting point analysis is one of the simplest and most useful techniques for identifing of a chemical substance. Melting point analysis can also provide information about the purity of a sample. A substance containing soluble impurities usually melts at a lower temperature than the pure compound. It can also melt over a wide range of temperatures. The smaller the range of melting temperatures, the higher the purity of the sample.</span>