volume_mute
There is an easy way to represent isotopes using the atomic symbols
publish date: 2022/09/18 04:19:00 GMT+10
volume_muteWe use the construction
A X Z
where (1) 
is the symbol of the element, (2) is the mass number, and (3) is the atomic number.
drag and drop the selected option to the right place or type it instead
X
A
Z
Correct Answer
(1) X
(2) A
(3) Z
Reference
Beginning Chemistry v. 1.0