In the nucleus of $$_{11}N{a^{23}},$$ the number of protons, neutrons and electrons are
A.
11, 12, 0
B.
23, 12, 11
C.
12, 11, 0
D.
23, 11, 12
Answer :
11, 12, 0
Solution :
A nucleus of mass number $$A$$ and atomic number $$Z$$ contains $$Z$$ protons and $$\left( {A - Z} \right)$$ neutrons. As an atom is electrically neutral, therefore number of peripheral electrons must be equal to $$Z,$$ the number of protons inside the nucleus. In $$_{11}N{a^{23}},Z = 11$$ i.e. number of protons = 11,
Mass number $$A = 23$$
Number of neutrons $$ = A - Z = 23 - 11 = 12$$
There is no electron in the nucleus. So, number of protons, neutrons and electrons are 11, 12, 0.
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