International General Certificate of Secondary Education (IGCSE) Chemistry Practice Exam

What is the charge of an electron?

1. +1

2. 0

3. -1

4. +2

The correct answer is: -1

The charge of an electron is negative one, denoted as -1. This fundamental property of electrons plays a crucial role in chemistry as it impacts the behavior of atoms and molecules. Electrons are subatomic particles that orbit the nucleus of an atom and carry a charge that is equal in magnitude but opposite in sign to that of a proton, which has a charge of +1. Understanding the negative charge of an electron is essential when considering how atoms bond with each other. For instance, the attraction between positively charged protons in the nucleus and negatively charged electrons is what keeps electrons in orbit around the nucleus, shaping the structure of atoms. Additionally, this charge is integral to the concepts of ionic and covalent bonding, where the transfer and sharing of electrons result in the formation of different types of compounds. Moreover, the charge of zero (0) represents neutrons, which have no charge and contribute to the mass of an atom but do not influence chemical bonding. A positive charge (+1) or +2 does not represent any stable subatomic particle within an atom but rather indicates a proton's charge or potential ionization states of atoms, respectively. Hence, the understanding of an electron's -1 charge helps form the basis for many topics in