Aluminum has 13 electrons, 13 protons and 14 neutrons
a) What is its atomic mass?
b) What is its atomic number?
c) What is its electronic configuration?
e) Will it take or give electrons?
d) What is its electronic configuration after electrons have been given or taken?
e) What is the charge on the atom after electrons have been exchanged?
The Correct Answer and Explanation is :
a) Atomic Mass:
The atomic mass of an element is the sum of the number of protons and neutrons in its nucleus. For aluminum (Al), the number of protons is 13 and the number of neutrons is 14. Therefore, the atomic mass is:
Atomic mass = Number of protons + Number of neutrons
[
Atomic \ mass = 13 + 14 = 27 \ u
]
So, the atomic mass of aluminum is 27 atomic mass units (u).
b) Atomic Number:
The atomic number is determined by the number of protons in the nucleus of an atom. For aluminum, it has 13 protons, so its atomic number is:
Atomic number = 13.
c) Electronic Configuration:
The electronic configuration of an element shows how its electrons are arranged in orbitals. Aluminum has 13 electrons, and we can use the following energy levels (shells) to distribute the electrons:
- First shell: 2 electrons
- Second shell: 8 electrons
- Third shell: 3 electrons
Thus, the electronic configuration of aluminum is:
[
1s^2 \ 2s^2 \ 2p^6 \ 3s^2 \ 3p^1
]
d) Will it take or give electrons?
Aluminum is in Group 13 of the periodic table, which means it has 3 electrons in its outermost shell (3p^1). Since atoms tend to be most stable when their outer electron shell is full (following the octet rule), aluminum will tend to give up its 3 valence electrons to achieve a stable electron configuration similar to the nearest noble gas, neon (Ne), with a full outer shell.
e) Electronic Configuration After Electrons are Given or Taken:
When aluminum gives away its 3 outermost electrons, it will have an electronic configuration like that of the nearest noble gas, neon (Ne), which has the configuration:
[
1s^2 \ 2s^2 \ 2p^6
]
Therefore, the electronic configuration after aluminum gives up 3 electrons is:
[
1s^2 \ 2s^2 \ 2p^6
]
This leaves the aluminum ion with a charge of +3, since it has lost 3 negatively charged electrons.
f) Charge on the Atom After Electrons are Exchanged:
Since aluminum has lost 3 electrons, it will have a net positive charge. The number of protons (13) remains unchanged, but the number of electrons is now 10. Therefore, the charge on the aluminum atom after losing 3 electrons is:
[
\text{Charge} = \text{Number of protons} – \text{Number of electrons} = 13 – 10 = +3
]
Thus, the charge on the aluminum ion after the exchange of electrons is +3.
Explanation:
Aluminum (Al) has an atomic number of 13, indicating 13 protons and 13 electrons in its neutral state. In its natural state, the electronic configuration is [Ne]3s^2 3p^1. However, to achieve a more stable state, aluminum typically loses its 3 valence electrons to match the stable configuration of neon (Ne), which has a completely filled second electron shell (1s^2 2s^2 2p^6). This results in the formation of an aluminum ion (Al^3+) with a +3 charge due to the loss of 3 negatively charged electrons.