Mass Number: Why Can It Be a Fraction?

  • Thread starter Thread starter kooyewyoung
  • Start date Start date
  • Tags Tags
    Mass
Click For Summary
SUMMARY

The discussion clarifies that the mass number of an atom, defined as the total number of protons and neutrons, is typically a whole number. However, due to the existence of isotopes, the mass number can appear as a fraction when considering atomic weight, which accounts for the relative abundance of isotopes. Participants emphasized the distinction between mass number and atomic weight, highlighting that while mass number is an integer, atomic weight can be a non-integer value due to the presence of isotopes.

PREREQUISITES
  • Understanding of atomic structure, specifically protons and neutrons
  • Familiarity with the concept of isotopes
  • Knowledge of the difference between mass number and atomic weight
  • Basic grasp of nuclear chemistry principles
NEXT STEPS
  • Research the concept of isotopes and their impact on atomic weight
  • Explore the differences between mass number and atomic weight in detail
  • Learn about how to calculate average atomic mass using isotopic abundance
  • Investigate the role of neutrons in nuclear stability and isotope formation
USEFUL FOR

Students studying chemistry, educators teaching atomic theory, and anyone interested in the nuances of atomic structure and isotopic variations.

kooyewyoung
Messages
1
Reaction score
0

Homework Statement


My instructor give me a question:
Mass number (number of protons and number of neutrons in an atom) is supposed to be a whole number for a particular atom, in reality IT IS NOT. Why is it so?

Homework Equations





The Attempt at a Solution


Here, I am very sure that this question ask for mass number (nucleon number) not atomic weight. However, how can only a part of a proton or neutron exist in an atom if mass number are not a whole number?
 
Last edited:
Physics news on Phys.org
Hint: Check out isotopes.
 
you are absolutely correct. Mass number is the NUMBER of neutrons and protons (nucleons)
This does not mean that the MASS is a whole number.
Like steamking I suggest you look at isotopes to get the idea of mass
 

Similar threads

  • · Replies 9 ·
Replies
9
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 7 ·
Replies
7
Views
2K
  • · Replies 4 ·
Replies
4
Views
2K
Replies
8
Views
2K
Replies
3
Views
2K
  • · Replies 1 ·
Replies
1
Views
1K
Replies
1
Views
1K
  • · Replies 2 ·
Replies
2
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K