Green chemistry - class-XI

Switching from air to pure oxygen eliminates NO production and also saves fuels by more efficient burning, thus, having less wastage. Hence, this is an application of Green chemistry.

Green chemistry also called sustainable chemistry, is an area of chemistry and chemical engineering, focused on the designing of products and processes that minimize the use of generation of hazardous substances.

The current commercial method for producing ibuprofen is a stunning application of green chemistry. Conventional methods of ibuprofen production requires six steps, hence, used large amounts of solvents and generated large amount of wastes. Current methods of ibuprofen production has just three steps and minimal waste, and is an application of Green chemistry.

Green chemistry seeks to develop products and processes that are kind to the environment. This can involve reducing the waste a process creates, using renewable materials, lessening the energy required to form a product, etc.
The given process is promoting renewable use of raw materials, hence, it is an objective of Green chemistry.

Green chemistry seeks to develop products and processes that are kind to the environment.
Plastics being developed from eco-friendly renewable sources, plus some modern plastics are biodegradable. The combination of innovations reduces our dependence on petroleum products, protects humans and wildlife from undesirable chemicals in old plastics, and reduces waste and impact on the environment.

All the three are objectives of Green chemistry.
1. Waste Prevention:   
It is better to prevent waste than to treat or clean up waste after it has been created.
2. Safer Solvents and Auxiliaries:    
The use of auxiliary substances (e.g., solvents, separation agents, etc.) should be made unnecessary wherever possible and innocuous when used.
3. Design for Energy Efficiency:    
Energy requirements of chemical processes should be recognized for their environmental and economic impacts and should be minimized. If possible, synthetic methods should be conducted at ambient temperature and pressure.

Use of petroleum creates lots of gases which are harmful to the environment. 

Pyrocool is a product which is environmentally benign foam discovered using concept of Green chemistry. Large-scale fires such as oil tankers and jet airplane can be extinguished in a short time and in a better way than previous use of the halons.

Green chemistry seeks to develop products and processes that are kind to the environment. This can involve reducing the waste a process creates, using renewable materials, lessening the energy required to form a product, etc.
Both the processes in the question involves forming products which are more friendly towards the environment. Hence, they are the applications of Green chemistry.

Since usage of petroleum-based plastic is harmful to the environment, a polymer called polylactic acid, made using micro-organisms to convert cornstarch into a resin, is used to preserve yogurt. The resulting polymer is used to replace rigid petroleum-based plastic used in yogurt containers and water bottles and is environment-friendly. It is an application of green chemistry

Green chemistry aims to reduce hazardous substances. Reacting methylamine and phosgene to produce methyl isocyanate is the process famously associated with the Bhopal disaster; it is highly toxic and definitely not an application of green chemistry.

Green chemistry, also called sustainable chemistry, is an area of chemistry and chemical engineering focused on the designing of products and processes that minimize the use and generation of hazardous substances.

Green chemistry is also known as environmentally sustainable chemistry. 

Solvents used to clean dry clothes are usually chlorinated compounds such as tetrachloroethylene $C _2Cl _4$ which is a human potential carcinogen which have serious environmental consequence. a substitute has been discovered which is environmental friendly is an application of green chemistry.

A toxic substance is a substance that can be poisonous or cause health effects.

Green chemistry seeks to develop products and processes that are kind to the environment. This can involve reducing the waste a process creates, using renewable materials, lessening the energy required to form a product, etc. 

Faraday has developed a plating process to make high-performance chrome coatings from trivalent chromium instead of highly toxic hexavalent chromium. It involves the production of alternate product which is more friendly to environment. Hence, this is an application of Green chemistry.

Green chemistry means chemistry that uses less harmful and hazardous chemicals products that does not cause any harm neither to us nor to the environment.

Green chemistry is a design of products and process that reduces or eliminates the use of harmful hazardous products. It uses the concept of invention and design and invokes to produce products that are environment-friendly.

Paraffin wax is a mixture of solid alkanes. It typically consists of long-chain hydrocarbons ranging from C21 to C30.

Alkaline hydrogen peroxide is used as a strong bleaching agent due to the oxidation state of $-1$ in the compound.

The first three compounds are chlorofluoro carbons which are harmful to ozone and unfriendly to the environment. These are used in refrigerators. so a compound called $CF _3CH _2F$ was discovered, which is friendly to the environment and used in refrigerators.

Urea is a major fertilizer used worldwide. It provides nitrogen to the soil by decomposing to ammonia and $CO _2$ when acted on by urease, an enzyme in soils. Then, ammonia is taken by the plants.