A Level Chemistry OCR Practice Exam

Which best defines an ionic bond?

1. An attraction between metal and non-metal ions

2. Electrons shared equally between two atoms

3. A force that results from a sharing of electrons

4. An interaction between polar molecules

The correct answer is: An attraction between metal and non-metal ions

An ionic bond is best defined as the attraction between metal and non-metal ions. This type of bond forms when an electron is transferred from a metal atom, which typically has a low electronegativity and easily loses electrons, to a non-metal atom, which has a high electronegativity and readily accepts electrons. The resulting ions created—cations from metals and anions from non-metals—are then held together by the strong electrostatic forces of attraction between the positively and negatively charged ions. This characteristic leads to the formation of ionic compounds, which typically exhibit properties such as high melting and boiling points, and electrical conductivity in molten or dissolved states. The other options describe different types of bonds or interactions, such as covalent bonds (where electrons are shared) or interactions between polar molecules, which do not fit the definition of an ionic bond.