Biological treatment is the primary method used to treat wastewater, utilizing microorganisms to break down organic matter.

The primary mode of heat transfer from the Sun to the Earth is radiation, as it travels through the vacuum of space.

In a vacuum, there are no particles to conduct or convect heat, so radiation is the only mode of heat transfer.

Convection is the primary mode of heat transfer in liquids and gases due to the movement of the fluid.

The primary mode of nutrition in the kingdom Animalia is heterotrophic.

Angiosperms primarily reproduce through sexual reproduction, involving flowers and seeds.

Ferns primarily reproduce through sexual reproduction, producing spores.

Polyethylene is primarily made from the polymerization of ethylene monomers.

Styrene is the primary monomer used to produce polystyrene.

The diaphragm is the primary muscle that contracts and relaxes to facilitate breathing.

The Bharat Rural Livelihoods Foundation was established to enhance livelihood opportunities for the rural poor, focusing on sustainable development.

The policy aims to enhance the employability of youth by providing them with necessary skills and training.

The primary objective of the National Policy on Disaster Management is to promote a culture of disaster preparedness and resilience among communities.

The Pradhan Mantri Awas Yojana aims to provide affordable housing to the urban poor and ensure housing for all by the year 2022.

In aluminum chloride, aluminum has an oxidation state of +3.

In carbon dioxide, carbon has an oxidation state of +4.

In potassium chloride, chlorine has an oxidation state of -1.

In NaCl, chlorine has an oxidation state of -1.

In CrO3, chromium has a primary oxidation state of +6.

Group 14 elements typically exhibit a +4 oxidation state in their compounds.

In FeCl3, iron (Fe) has a primary oxidation state of +3.

In KMnO4, manganese has an oxidation state of +7.

In MnO4-, manganese has an oxidation state of +7.

In ammonia, nitrogen has an oxidation state of -3.

In nitric acid, nitrogen has an oxidation state of +5.

In sulfuric acid (H2SO4), sulfur has an oxidation state of +6.

Ozone is a key component of photochemical smog, formed by the reaction of sunlight with pollutants like nitrogen oxides.

Particulate matter is a primary pollutant in smog, contributing to air quality issues.

Spectroscopy relies on the absorption of light by substances, which can be used to identify different groups based on their unique absorption spectra.

Photosynthesis is the primary process by which energy from sunlight is converted into chemical energy by plants.