Answer:
14amu
Explanation:
Given subatomic particles:
Number of protons = 7
Number of Neutrons = 7
Number of electrons = 7
Unknown:
Atomic mass unit; amu of nitrogen
Solution:
The atomic mass unit of a substance is the number of protons and neutrons in such an atom;
Atomic mass unit = number of protons + number of neutrons
This is because the mass of an atom is concentrated in the nucleus;
For the given specie;
Atomic mass unit = 7 + 7 = 14amu