Explanation

The K orbit, also known as the first electron shell.

• It can hold a maximum of 2 electrons.

The L orbit, also known as the second electron shell.

• It can hold a maximum of 8 electrons.

The M orbit, also known as the third electron shell.

• It can hold a maximum of 18 electrons.

Last verified on 19-03-2026

Explanation

• The mass number (A) is the sum of protons and neutrons present in the nucleus of an atom.
• It is a measure of the total number of nucleons (protons and neutrons) in the nucleus.
• It helps determine the atomic mass and distinguishes isotopes of an element.

Last verified on 19-03-2026

Explanation

• Halazone tablets are used to purify drinking water by killing bacteria and pathogens.
• Commonly used in emergencies, military, or travel situations where safe water is unavailable.
• Halazone tablets can purify 1 liter of water in about 5–10 minutes.

Last verified on 19-03-2026

Explanation

• About 97.5% of the water on Earth is saltwater, found in oceans, seas, and salt lakes.
• The remaining 2.5% is freshwater, found in rivers, lakes, wetlands, and underground aquifers.

Last verified on 19-03-2026

Explanation

• Cat and Dog is/are a secondary consumer.
• Because they eats primary consumers (herbivores).
• Like mice, birds, and rabbits.

Last verified on 19-03-2026

Explanation

• If an object absorbs all seven colors of light (i.e., all the wavelengths of visible light), it appears black.
• This is because no light is being reflected, and our eyes perceive the absence of light as black.
• When an object reflects all the component colors of light, it appears white.

Last verified on 18-03-2026

Explanation

• Security mirrors are typically convex mirrors.

The examples of concave mirrors:

• Cosmetic mirrors (makeup mirrors)
• Dentist mirrors
• Car headlight mirrors

Last verified on 18-03-2026

Explanation

• A kaleidoscope is an optical instrument that creates symmetrical, colorful multiple images using mirrors and colored objects.
• When rotated, it continuously forms new patterns of images.
• Commonly used for educational purposes and toys.

Last verified on 18-03-2026

Explanation

• Reflection occurs when light bounces back from a surface instead of passing through it.
• Shiny or smooth surfaces like mirrors produce clear and regular reflections.
• This principle is used in mirrors, periscopes, and optical instruments.

Last verified on 18-03-2026

Explanation

• A saturated solution contains the maximum amount of solute that can dissolve at a given temperature.
• Any additional solute added will remain undissolved.
• Example: Sugar in water at room temperature reaches saturation when no more sugar dissolves.
• If a solution contains less solute than the maximum, it is called unsaturated.

Last verified on 18-03-2026