Why does the chloride ion have a -1 charge?
a
Chlorine atoms lose an electron.
b
Chlorine atoms share electrons.
c
Chlorine atoms have no electrons.
d
Chlorine atoms gain an electron.
d) Chlorine atoms gain an electron.
The correct answer is d) Chlorine atoms gain an electron.
Chlorine belongs to Group 17 (also known as Group VIIA) of the periodic table, which is commonly referred to as the halogens. The halogens have seven valence electrons, which means they are only one electron short of having a stable, full outer shell of 8 electrons. In order to achieve a stable state, chlorine atoms tend to gain one more electron from other atoms or molecules.
By gaining one electron, the chlorine atom achieves a full outer shell, similar to the structure of the noble gas argon. This extra electron leads to an overall negative charge on the chlorine ion, making it a chloride ion with a -1 charge.
To determine the charge of an ion, it is important to understand the concept of electron transfer. In this case, chlorine atoms gain one electron to become chloride ions with an overall negative charge. This process is driven by the need to attain a stable electron configuration and achieve a lower energy state.
The correct answer is d) Chlorine atoms gain an electron.
Chlorine atoms in their neutral state contain 17 protons and 17 electrons. In order to achieve a stable electron configuration, chlorine atoms tend to gain one electron from other atoms. This results in the formation of chloride ions (Cl-) which have an extra electron compared to the neutral chlorine atom, giving it a -1 charge. The gained electron fills the outermost energy level of the chlorine atom, making it more stable.