Which statement best describes the nucleus of an aluminum atom?
(1) It has a charge of +13 and is surrounded by a total of 10 electrons.
(2) It has a charge of +13 and is surrounded by a total of 13 electrons.
(3) It has a charge of –13 and is surrounded by a total of 10 electrons.
(4) It has a charge of –13 and is surrounded by a total of 13 electrons.
The answer is (2). The atomic number of Al atom is 13 which means that there is 13 protons in the nucleus. So the nucleus has a charge of +13. And the Al atom has net charge of 0. So there is 13 electrons surrounded the nucleus.
