Ionic compounds have high melting and boiling points because a substantial amount of energy is required to break the strong inter-ionic attractions present in their crystal lattice structure.

Ionic compounds are hard and brittle due to the strong force of attraction between the positive and negative ions, leading to the formation of a rigid crystalline structure.

Iron filings burn vigorously due to their fine particle size, enhancing reactivity with oxygen. Copper, when heated, does not burn, but it forms a black-colored layer of copper(II) oxide on its surface.

The thin layer of oxide acts as a protective layer, preventing further oxidation of the metal at ordinary temperatures.

Metals like potassium and sodium react vigorously with oxygen and can catch fire if exposed to air. Keeping them immersed in kerosene oil prevents accidental fires and protects them from reacting with atmospheric oxygen.

Carbon exists in different forms called allotropes. Diamond, the hardest natural substance with a high melting and boiling point, and graphite, a conductor of electricity, are two allotropes of carbon.

Iodine, despite being a non-metal, exhibits luster, which is a characteristic property of metals.

Electric wires are coated to insulate and protect against electric shock. Metals that produce a sound on striking a hard surface are termed sonorous.

Metals such as copper, aluminum, and stainless steel are commonly used for making cooking vessels because of their malleability, ductility, good heat conductivity, and high melting points.

The ability of metals to be drawn into thin wires is known as ductility, and gold is mentioned as the most ductile metal.