Explanation

Air is a mix of gases, with nitrogen (78%) and oxygen (21%) being the main components.

The plus trace amounts of other gases like argon, carbon dioxide, and water vapor.

Explanation

Ugly means بدصورت

Beautiful means خوبصورت

Explanation

The pH scale ranges from 1 to 14, with:

• 1-6 being acidic
• 7 being neutral (neither acidic nor basic)
• 8-14 being basic (alkaline)

Explanation

Atomic nuclei consist of electrically positive protons and electrically neutral neutrons.

The nucleus makes up much less than. 01% of the volume of the atom,

but typically contains more than 99.9% of the mass of the atom.

Explanation

Pakistan is located in the western part of South Asia.

It shares borders with India to the east, Afghanistan and Iran to the west, and China to the north.

Explanation

Chlorine is a strong oxidant that rapidly kills many harmful microorganisms.

Chlorine is a toxic gas.

Explanation

Chlorophyll is the green pigment responsible for photosynthesis, and it is primarily contained in the mesophyll cells of plant leaves.

These cells are located in the middle layer of the leaf.

They are the main site for photosynthesis.

Explanation

The 4R-8R (48) Principle stands for a combination of strategies like Refuse, Reduce, Reuse, Recycle and 8 more Rs (like Rethink, Repair, Recover, etc.).

It is applied to minimize pollution caused by non-biodegradable waste by promoting sustainable practices.

Explanation

Convection is the transfer of heat through the movement of fluids (liquids or gases) due to differences in temperature and density.

It does not occur in solids as the particles in solids are not free to move.

Explanation

Three Primary Colors : Red, Yellow, Blue.

Three Secondary Colors : Orange, Green, Violet.

Six Tertiary Colors : Red-Orange, Yellow-Orange, Yellow-Green, Blue-Green, Blue-Violet, Red-Violet,

which are formed by mixing a primary with a secondary.