What type of bond is formed when electrons are transferred from one atom to another?

• A. Ionic bond
• B. Covalent bond
• C. Hydrogen bond
• D. Polar

Answer: (A)

When electrons are transferred from one atom to another, ions are created: a positively charged cation from the atom that loses electrons and a negatively charged anion from the atom that gains them. The strong electrostatic attraction between these oppositely charged ions binds them together, forming an ionic bond. This is different from covalent bonds, where electrons are shared between atoms rather than moved completely from one to another. Ionic compounds tend to form crystalline lattices and usually have high melting points; they also conduct electricity when dissolved in water or melted, because the charged ions can move freely. The term polar refers to unequal distribution of electron density in a molecule, which leads to partial charges, but it does not describe a bond formed by transferring electrons. So the concept tested is the transfer of electrons producing ions that attract each other to create an ionic bond.