Answer:
its atomic number
Explanation:
the mass number/atomic mass is how many protons and neutrons are combined in an element. But, the atomic number is just protons.
Hello Mate!Well, there are
many definitions and descriptions of isolated systems, and
here are some of them:
1.
It can be a physical system which is located very very far from all other systems, so there is absolutely no interaction between them, thus making it isolated.
2.
It can be a thermodynamic system with rigid walls, which prevents mass and energy to pass through.
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