Question

In which type of bond do atoms share electrons? A. metallic C. ionic B. hydrogen D. covalent

Short answer

Covalent bonds involve sharing electrons.

Step-by-step solution

Understanding Bond Types

Start by examining the common types of chemical bonds. Atomic bonds are interactions between atoms that can transfer or share electrons to achieve stability. The primary bond types are metallic, ionic, hydrogen, and covalent.

Defining Covalent Bonds

A covalent bond forms when two atoms share one or more pairs of electrons. This sharing allows both atoms to achieve a stable electron configuration, similar to noble gases.

Examine Other Bonds

Metallic bonds involve a sea of shared electrons around metal cations, allowing for conductivity and malleability. Ionic bonds occur when an atom donates one or more electrons to another, resulting in attraction between oppositely charged ions. Hydrogen bonds are intermolecular forces rather than true bonds, primarily affecting molecular compounds like water.

Conclusion

Since covalent bonds involve the sharing of electrons between atoms, the correct answer is D. Covalent.

Key concepts

Covalent Bond

A covalent bond forms when two atoms come together and share one or more pairs of electrons. This type of bond is most typically found between nonmetal atoms. The sharing of electrons allows each atom to attain the electron configuration of a noble gas, achieving stability. Covalent bonds can be single, double, or triple, depending on how many electron pairs are shared.

• Single Bond: Involves one shared pair of electrons.
• Double Bond: Involves two shared pairs of electrons.
• Triple Bond: Involves three shared pairs of electrons.

The strength and length of the covalent bond depend on the number of shared electrons. More shared electrons typically mean a stronger and shorter bond.

Electron Sharing

Electron sharing is the foundational concept behind covalent bonding. It involves two atoms holding onto each other's electrons. Instead of complete electron transfer, as seen in ionic bonds, these electrons are shared jointly by the atoms, allowing them to maintain a stable structure. Through sharing, atoms get the benefit of a complete valence shell, similar to noble gases. This is why molecules like O extsubscript{2} are formed, as each oxygen atom shares two electrons with the other, creating a double bond. Understanding electron sharing helps explain why certain molecules exist and how they interact with each other.

Ionic Bond

Ionic bonds are interactions that occur when one atom transfers electrons to another. Unlike covalent bonds, where electrons are shared, ionic bonds are based on electron donation. These bonds usually form between metal and nonmetal atoms. The donating atom (which becomes a cation) loses electrons to the receiving atom (which becomes an anion). The strong electrostatic attraction between the oppositely charged ions forms the ionic bond. For example, in sodium chloride (NaCl), the sodium atom donates an electron to chlorine, resulting in a positively charged sodium ion and a negatively charged chloride ion. This type of bond is often found in salts and is responsible for their many properties, such as high melting and boiling points.

Hydrogen Bond

Hydrogen bonds are unique because they are not true bonds but rather forces of attraction between molecules. Despite this, they play a significant role in determining the properties of substances. They occur when hydrogen is covalently bonded to an electronegative atom (like oxygen or nitrogen) and experiences an attraction to another electronegative atom.

• They are weaker than ionic and covalent bonds, but crucial in biological contexts.
• Responsible for the special properties of water, such as its high boiling point and surface tension.
• Important for the structure of proteins and DNA.

Hydrogen bonds are key in many biological and chemical processes, influencing everything from liquid cohesion to the shapes of complex molecules.