The chemical symbol of the element is represented by X in the atoms given below:

¹³⁰₅₆X    ¹²⁸₅₄X    ¹³⁹₅₇X    ¹²⁶₅₂X    ¹³⁰₅₄X

Determine which atoms have an equal number of neutrons.

The mass numbers of the two naturally occurring isotopes of rhenium are 185 and 187. Provide the isotopic symbol for each.

The chemical symbol of the element is represented by X in the hypothetical atoms listed below:

Identify which hypothetical atoms have equal mass numbers.

Three isotopes of silicon, with mass numbers of 28, 29, and 30, exist naturally. How are these isotopes different?

 Certain isotopes of boron and chlorine are given below. Identify the number of protons and neutrons in each isotope. 

1. boron-11        

2. chlorine-35      

3. chlorine-37