1. Carbon exists in diverse forms with distinct properties. Diamond, composed of tetrahedrally bonded carbon atoms, is exceptionally hard and a poor conductor of electricity. Graphite, with hexagonal layers held by weak forces, is a solid lubricant and conducts electricity. Graphene, a single layer ofRead more

    Carbon exists in diverse forms with distinct properties. Diamond, composed of tetrahedrally bonded carbon atoms, is exceptionally hard and a poor conductor of electricity. Graphite, with hexagonal layers held by weak forces, is a solid lubricant and conducts electricity. Graphene, a single layer of hexagonally arranged carbon atoms, exhibits remarkable electrical conductivity and strength. Carbon nanotubes, cylindrical structures made of rolled-up graphene sheets, possess excellent electrical, thermal, and mechanical properties. Fullerenes, spherical carbon molecules like buckyballs (C60), have unique properties and applications in medicine and materials science. This diversity stems from variations in carbon bonding and structure.

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  2. Potassium and sodium, being highly reactive alkali metals, react vigorously with oxygen and moisture in the air. To prevent their exposure to these elements, potassium and sodium are kept immersed in kerosene oil. Kerosene creates a protective layer, preventing contact with atmospheric oxygen and waRead more

    Potassium and sodium, being highly reactive alkali metals, react vigorously with oxygen and moisture in the air. To prevent their exposure to these elements, potassium and sodium are kept immersed in kerosene oil. Kerosene creates a protective layer, preventing contact with atmospheric oxygen and water vapor. If exposed, these metals can undergo rapid oxidation and react violently, sometimes leading to combustion or explosion. By storing them in kerosene, a non-reactive hydrocarbon liquid, the metals remain isolated from the air, ensuring their stability and safety for handling and storage in laboratory or industrial settings.

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  3. The thin layer of oxide on the surfaces of metals like magnesium, aluminium, zinc, and lead at ordinary temperatures acts as a protective barrier. This oxide layer forms upon exposure to air and prevents further corrosion or oxidation of the underlying metal. The oxide layer serves as a physical andRead more

    The thin layer of oxide on the surfaces of metals like magnesium, aluminium, zinc, and lead at ordinary temperatures acts as a protective barrier. This oxide layer forms upon exposure to air and prevents further corrosion or oxidation of the underlying metal. The oxide layer serves as a physical and chemical barrier, inhibiting the metal’s reaction with oxygen and moisture in the environment. This protective coating enhances the metals’ resistance to corrosion, maintaining their integrity and preventing deterioration. Regular atmospheric exposure allows these metals to passivate and develop a stable oxide layer, ensuring their durability in various applications.

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  4. Iron filings burn vigorously when sprinkled in the flame of a burner due to the combustion of finely divided iron. The increased surface area of the filings promotes rapid oxidation, combining with oxygen in the air to form iron oxide (rust) with the release of energy. When copper is heated, it undeRead more

    Iron filings burn vigorously when sprinkled in the flame of a burner due to the combustion of finely divided iron. The increased surface area of the filings promotes rapid oxidation, combining with oxygen in the air to form iron oxide (rust) with the release of energy.
    When copper is heated, it undergoes a color change. Initially, it has a metallic pinkish hue, but as it gets hotter, it turns to a reddish color, eventually developing a dark brown or black coating. This change is due to the formation of copper oxide on the surface, indicating the reaction of copper with oxygen in the air (oxidation).

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  5. The high melting and boiling points of ionic compounds are primarily attributed to the strong electrostatic forces of attraction between positively and negatively charged ions. In ionic compounds, such as salts, ions are held together by ionic bonds, formed through the transfer of electrons from oneRead more

    The high melting and boiling points of ionic compounds are primarily attributed to the strong electrostatic forces of attraction between positively and negatively charged ions. In ionic compounds, such as salts, ions are held together by ionic bonds, formed through the transfer of electrons from one element to another. These bonds create a three-dimensional lattice structure, and breaking them requires a significant amount of energy. As a result, ionic compounds have high melting and boiling points because substantial heat is needed to overcome the strong electrostatic forces and break the bonds, transitioning the compound from a solid to a liquid or gas state.

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