* Atoms are normally neutral: Atoms contain an equal number of protons (positively charged particles) and electrons (negatively charged particles). This balance results in a neutral charge.
* Gaining electrons: When an atom gains one or more electrons, it acquires a surplus of negative charge. The number of electrons now exceeds the number of protons, making the atom negatively charged.
* Ions: A negatively charged atom is called an anion.
How atoms gain electrons:
* Chemical bonding: Atoms can gain electrons by forming chemical bonds with other atoms. For example, in an ionic bond, one atom loses an electron while another gains it.
* Electrostatic interactions: An atom can gain an electron from another atom or molecule through electrostatic interactions. This can occur in solutions or when exposed to radiation.
Example:
* A chlorine atom (Cl) has 17 protons and 17 electrons.
* It can gain an electron to form a chloride ion (Cl-), which now has 17 protons and 18 electrons.
* This extra electron gives the chloride ion a negative charge.
