The sodium atom has an atomic number of 11 and an atomic weight of 23.The neutral atom contains
A)11 neutrons and 12 protons.
B)11 protons and 12 neutrons.
C)12 electrons and 11 neutrons.
D)23 protons and 12 electrons.
E)23 electrons and 12 neutrons.

Question

Quizplus · Accepted Answer

The atomic number of 11 indicates that there are 11 protons in the nucleus of the sodium atom. The atomic weight of 23 indicates that the sum of protons and neutrons in the nucleus is 23. Since the atom is neutral, the number of electrons must also be 11. Therefore, the sodium atom contains 11 protons and 12 neutrons. Choice B is the only option that reflects this.

The Sodium Atom Has an Atomic Number of 11 and an Atomic