Question

What is different for isotopes of uranium?

• A. Number of protons
  
• B. Numbers of planetary electrons
• C. Atomic masses
  
• D. Atomic numbers

Answer 1

The correct option is C Atomic masses

Atomic masses are different for isotopes of uranium.
Different isotopes of uranium have a different number of neutrons and different atomic masses. They have the same atomic number, the same number of electrons and same number of protons. For example, the atomic number of $U$ is $93$. Two isotopes of uranium have mass numbers $235$ and $238$ respectively.