Explanation

• The atomic number (Z) is the number of protons present in the nucleus of an atom.
• It determines the identity of an element.
• It is a unique identifier for each element.

Explanation

• Diffused reflection occurs when parallel rays of light hit a rough surface, scattering in different directions.
• This type of reflection is characterized by a random change in direction of the reflected light, resulting in a diffuse or scattered beam.

Examples:

• Wall
• Paper
• Cloth
• Cardboards

Explanation

• A gear (cog) is a toothed wheel that meshes with other gears to transmit rotational motion or change the direction of force.
• The pointed edges like teeth are used to engage with other gears and transmit power.

Explanation

• Suspensions are mixtures in which the solute particles are dispersed throughout the solvent, but are not dissolved.
• The particles are visible to the naked eye and settle out of the mixture over time.
• Examples: Muddy water, milk and blood.

Explanation

• Salt (a solid) dissolves in water (a liquid) to form a solution.
• Making it a classic example of a solid-liquid solution.

Explanation

• Stomata are small openings on the surface of leaves that allow for gas exchange.
• Including the release of water vapor (transpiration) and the entry of carbon dioxide.
• This process is essential for photosynthesis and regulation of water balance in plants.

Explanation

• Jupiter is a non-luminous object.
• Unlike burning coal, glassware and fireworks, which either emit or reflect light in ways that are noticeable.
• Jupiter does not generate its own light but reflects the light of the Sun.

Explanation

Matter changes state from:

• Solid to liquid (melting) when it gains energy
• Liquid to gas (vaporization) when it gains energy

This is because the particles need more energy to break free from their rigid structure in solids and move more freely in liquids, and even more energy to escape into the air as gases.

Explanation

• Vegetable waste from farms is an example of biodegradable waste.
• Which can be broken down naturally by decomposers such as bacteria, fungi, and other microorganisms.

Explanation

Land pollution is caused by:

• Plastic bags, bottles, glass bottles, tin cans
• Vegetables and fruit cutting
• Animal wastes