Machine-translated by Google. Questions are authored in English.
Top

Discussion

The mass number of a nucleus is

  • A.Always less than its atomic number
  • B.The sum of the number of protons and neutrons present in the nucleus
  • C.Always more than the atomic weight
  • D.A fraction

Answer: B

The mass number is the sum of the protons and neutrons in the nucleus, together called the nucleons.

It is always a whole number and is at least equal to the atomic number, which counts protons only. Atomic weight, by contrast, is an average over the natural isotopes and so is usually fractional.

No comment is present. Be the first to comment.
Loading…

Post your comment

Please log in or register to post a comment.