Relative atomic mass of an element ?

In summary, the relative atomic mass of an element can be calculated by taking the percentage of each isotope present and dividing it by 100. This accounts for the fact that some elements have isotopes with different masses, resulting in non-whole number relative atomic masses. In the conversation, the relative atomic mass of neon was calculated to be approximately 20.16.
  • #1
faisal
46
0
relative atomic mass of an element ?

A sample of neon was found to cotain 90.9% of 20Ne, 0.26% of 21Ne, & 8.8% of 22Ne, Calculate the relative atomic mass of neon.
this is what i'v done so far (90.9x 20)+ (0.26x21)+(8.8x22)= 2017/?
i don't know what to divide it by :confused: ? I'm not given a mass spectra?
P.s.
why r relative atomic masses for some elements not whole numbers, is it because they r isotopes?
 
Chemistry news on Phys.org
  • #2
Divide by 100.

That will get you 20.17

Yes, they are not whole numbers because of isotopes. That's what you're taking account for by finding the relative atomic mass.
 
  • #3
Thanx, i did the question again and i got 20.16 this is what i did (90.9/100x20)+(0.26/100x21)+(8.8/100x22)= 20.16
 
  • #4
Either way works. :)
 

What is the relative atomic mass of an element?

The relative atomic mass of an element is the average mass of all the isotopes of that element, taking into account their abundance.

How is the relative atomic mass of an element calculated?

The relative atomic mass of an element is calculated by multiplying the mass of each isotope by its relative abundance and then adding all of these values together.

Why is the relative atomic mass of an element not a whole number?

The relative atomic mass of an element is not a whole number because it takes into account the different masses and abundances of the isotopes. Some isotopes are more abundant than others, resulting in a weighted average that is not a whole number.

What is the difference between relative atomic mass and atomic mass?

Atomic mass is the mass of a specific isotope of an element, while relative atomic mass is the average of all the isotopes of an element. Atomic mass is a specific value, while relative atomic mass is a weighted average.

Why is the relative atomic mass of an element important?

The relative atomic mass of an element is important because it is used to calculate other important values, such as the molar mass and the number of moles of a substance. It also helps in identifying and characterizing elements and their properties.

Similar threads

Why wasn't fluorine used as a standard for atomic mass?
    • Chemistry
Replies
6
Views
2K
B Factors contributing to the atomic mass of an atom
    • Atomic and Condensed Matter
Replies
3
Views
4K
Atomic Mass of Element X: Solving with John Dalton Ratios
    • Biology and Chemistry Homework Help
Replies
13
Views
3K
Isotopes, atomic mass, abundance
    • Biology and Chemistry Homework Help
Replies
1
Views
2K
Empirical formula from mass percentage.
    • Chemistry
Replies
1
Views
2K
Finding the Equilibrium Temperature
    • Advanced Physics Homework Help
Replies
1
Views
2K
What is the difference between atomic mass and molar mass in chemistry?
    • Chemistry
Replies
1
Views
3K
Bromine Isotopes: Mass, Atomic Mass & Percent Abundance
    • Biology and Chemistry Homework Help
Replies
2
Views
7K
Atomic Mass of Neon: Explained for High School Chemistry
    • Chemistry
Replies
3
Views
3K
Finding the unknown atomic mass of element X
    • Biology and Chemistry Homework Help
Replies
1
Views
6K

Hot Threads

Recent Insights

Back
Top