Humber Admissions Practice Test

What is the primary characteristic of a covalent bond?

1. Atoms exchange protons

2. Atoms share electrons

3. Atoms form ionic connections

4. Atoms attract completely opposite charges

The correct answer is: Atoms share electrons

The primary characteristic of a covalent bond is that atoms share electrons. In a covalent bond, two atoms come together and share one or more pairs of electrons in order to achieve stability, often aiming for a complete outer electron shell. This sharing allows each atom to attain a full complement of electrons similar to that of noble gases, which are known for their stability. In contrast, other interactions such as ionic bonds involve the transfer of electrons rather than sharing, where one atom donates an electron to another, resulting in the formation of charged ions. The attraction of completely opposite charges describes ionic interactions but does not apply to covalent bonds. Additionally, the exchange of protons does not occur in covalent bonding; rather, it is a feature of nuclear reactions. Thus, the only accurate description of what occurs in covalent bonding is the sharing of electrons.