Respuesta :
Answer:
Lithium has 4 neutrons
Explanation:
The number shown above the lithium symbol (Li) is the mass number.
The mass number (A) represents the protons and neutrons an atom has.
The atomic number(Z) in the other hand represents the protons only.
So, the difference between this two numbers is the amount of neutrons.
[tex]n_{neutrons}=A-Z=7-3=4[/tex]