28. Green Chemistry – why it matters?
Lights off! Candles on!
Let us recall the day when Earth Hour was celebrated… Did you switch off all the lights? Even so, do you practice this habit constantly when we leave the room after its usage? If so, you are practising environmental sustainability. Good Job, because you are doing your part in practising responsibility for our planet given its limited resources. However, is this the only habit that will ensure that our planet is sustainable for our future generations? I doubt so! Chemists use green chemistry to assess the sustainability and environmental impacts of manufactured chemical processes. These chemists think about the chemical impact that rises starting from the laboratory, ranging to the disposal site, finally ending at the environment where it is released. One method they can evaluate these impacts would be with the 12 principles of Green Chemistry. Our chemistry tuition will introduce these concepts and guide you to remember these 12 principles with ease.
The 12 Principles of Green Chemistry
Although it is known as principles of “Chemistry”, this principle in fact applies to many aspects of real life. It forms the first rule of the famous 3R’s which is to “REDUCE” the amount of waste being produced. While people try to apply this principle by producing less waste at home, Chemists utilise this principle by attempting to reduce the volume of chemical waste production. As such, one of the principles of green chemistry would be waste prevention. Let us take a car as an example. Inside a car’s engine, fuel and oxygen would undergo combustion, which then produces energy needed to move the car. This eventually results in harmful byproducts such as carbon monoxide, nitrogen oxides and volatile organic compounds. These altogether would contribute to smog, further causing respiratory illnesses amongst people. However, cars also contain catalytic converters which chemically changes these pollutants to harmless molecules before being released into the atmosphere. Some examples of these harmless molecules include oxygen, water and carbon dioxide. Join our chemistry tutor’s lessons to figure out what interesting scenarios our chemistry tutor has to offer for the other 11 principles of Green Chemistry.
Application of Green Chemistry
While reducing waste with minimal damage to the environment is important, green chemistry also reduces the pollution released from its source, in order to conserve the Earth’s chemical and biological resources, such as energy. This becomes particularly important in the pharmaceutical industry, which involves many potentially polluting solvents. When designing and producing new drugs in the pharmaceutical industry, aiming for a high atom economy is important. This concept of atom economy simply refers to the ratio of the total mass of the desired product to the total mass of all the products. This is generally a measure of how much reactants remain in the final product.
Atom Economy = (mass of atoms in desired product/mass of atoms in reactants) x 100%
When our parents visited the dentist for toothache, they were most probably prescribed a painkiller known as Ibuprofen. This is actually an example of green chemistry. The original method used to manufacture and prepare Ibuprofen was wasteful and inefficient, because only 40% of the atoms used to make the product was made as the final product. Unhappy with the results, the manufacturer in the 1990s, devised and developed a new process, which incorporated a few of the principles of green chemistry. Since then, 77% of the atoms are being made into the final product. This invention eventually earned the manufacturer a ‘Green Chemistry Challenge Award’ in the United States in 1997. Are you going to challenge yourself for such awards in the future? Stay with our chemistry tutor to find out how Green Chemistry is being used in our daily life activities and inventions!
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