If an atom has 3 protons, 3 neutrons, and 2 electrons, what is the electrical charge of the atom?
The Correct Answer and Explanation is:
The electrical charge of an atom is determined by the difference between the number of protons and electrons it has.
In this case, the atom has:
- 3 protons, which each have a +1 charge.
- 3 neutrons, which have no charge (neutral).
- 2 electrons, which each have a -1 charge.
To find the overall charge of the atom, we subtract the number of electrons from the number of protons:Charge=Number of protons−Number of electrons\text{Charge} = \text{Number of protons} – \text{Number of electrons}Charge=Number of protons−Number of electronsCharge=3−2=+1\text{Charge} = 3 – 2 = +1Charge=3−2=+1
This means the atom has a positive charge of +1.
Explanation:
- Protons carry a positive charge, so their presence gives the atom a positive charge.
- Electrons carry a negative charge. If an atom has more electrons than protons, it will have a negative charge, and if it has more protons than electrons, it will have a positive charge.
- Neutrons do not affect the electrical charge because they are neutral.
Since the number of protons (3) is greater than the number of electrons (2), the atom is positively charged, and its charge is +1. This type of atom is called an ion, specifically a cation, because it has lost one electron compared to its neutral state.
A neutral atom of this element (which is lithium, Li) would normally have 3 electrons to balance the 3 protons. However, with 2 electrons, the atom has a net positive charge.
