Materials whose atoms feature tightly bound electrons are best described as:

Materials whose atoms feature tightly bound electrons are best described as:

• A. Conductors
• B. Metals
• C. Gases
• D. Insulators

Answer: (D)

When electrons are tightly bound to their atoms, they don’t move freely in response to an electric field. With few or no mobile charge carriers available, applying a voltage produces only a tiny current. That describes an insulating material, which resists electrical conduction because its electrons stay localized and require a large amount of energy to become free to carry charge. In contrast, conductors have electrons that can move easily, often due to a “sea” of delocalized electrons in metals, which allows current to flow readily. Gases at room conditions are generally poor conductors because particles are far apart and there aren’t many free charges, unless the gas is ionized.

When electrons are tightly bound to their atoms, they don’t move freely in response to an electric field. With few or no mobile charge carriers available, applying a voltage produces only a tiny current. That describes an insulating material, which resists electrical conduction because its electrons stay localized and require a large amount of energy to become free to carry charge.

In contrast, conductors have electrons that can move easily, often due to a “sea” of delocalized electrons in metals, which allows current to flow readily. Gases at room conditions are generally poor conductors because particles are far apart and there aren’t many free charges, unless the gas is ionized.