2018-02-13
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Some of the observable examples of chemical reactions in everyday life are respiration (aerobic and anaerobic), photosynthesis, rusting and burning. Read on to find out...
Decomposition of carbonic acid
Look at the things around you, nearly all of them are made up of some sort of substances, which are further classified into element, mixture, alloy, etc. And speaking in chemistry terms, the air we breathe is a mixture in gaseous state, while water is a compound existing in liquid state. Considering the abundance of substances in and around us, it is not unusual to observe examples of chemical reactions in everyday life. Before we discuss the chemical reactions that occur in everyday, let's try to understand what actually takes place a chemical reaction.
What are Chemical Reactions?
A chemical reaction is defined as the process, wherein a set of chemical substances react with each other, which leads to their conversion into other different forms. The initial substances used the reaction are collectively called reactants, while the final substances formed after the reaction are known a products. In general, the chemical properties of the reactants and products are different from each other. Based on whether the reaction is initiated with energy or without energy, it is classified into two types, spontaneous reaction (that occurs on its own) and non-spontaneous reaction (require energy for activation).
Some Chemical Reactions in Everyday Life
Science being a subject of common interest, it is very intriguing to analyze visual experiments happening in day-to-day life. There are a plethora of products that you use everyday, which are formulated with application of chemical reaction. Say for example; toothpaste, soap, shampoo, cleaning agent, etc. are all results of chemical reactions. Following are some of the most profound chemical reactions, which we encounter in everyday life:
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Aerobic Respiration
Do you know indulging in physical movements is associated with a chemical reaction? The process requires energy, which is yielded by aerobic respiration. Over here, respiration helps breaks down glucose (an energy source) into water, carbon dioxide and energy in form of ATP (adenosine triphosphate). The balanced cellular respiration equation is represented as:
C6H12O6 + 6O2 → 6CO2+ 6H2O + Energy (36 ATPs)
Anaerobic Respiration
Due to overexercising, sometimes our body cells run out of oxygen and respire anaerobically. This cause synthesis of lactic acid and cause muscle cramps. Anaerobic respiration is observed in some bacteria, yeast and other organisms. In contrary to the aerobic type, it breaks down glucose in the absence of oxygen, resulting in production of ethanol, carbon dioxide and energy. Anaerobic respiration equation is:
C6H12O6 → 2C2H5OH + 2CO2 + Energy
Photosynthesis
Photosynthesis is the process by which green plants manufacture their own food. This occurs in presence of sunlight and other raw materials, namely carbon dioxide and water. The chlorophyll pigment harvests the light energy from sunlight, which is then converted into glucose by the phenomenon of photosynthesis. In short, it is the opposite of aerobic respiration. The equation for photosynthesis is:
6 CO2+ 6 H2O + Light energy → C6H12O6 + 6 O2
Rusting of Iron
Very often, you notice a coating of rust over unpainted iron surfaces, which gradually leads to disintegration of iron. This is nothing, but a chemical phenomenon called rusting. In this case, iron (a very reactive metal) combines with oxygen in presence of water (more precisely, atmospheric moisture), resulting in formation of iron oxides. The chemical reaction behind rusting can be simply represented as:
Fe + O2 + H2O → Fe2O3. XH2O
Propane Grill
Have you ever prepared meat in a propane grill? The meat placed over the burner is cooked with the help of heat energy released after burning of propane gas. Thus, propane is the reactant which when burnt with the help of oxygen gives heat energy and other byproducts. Check out the balanced equation for the combustion reaction that take place in a propane grill:
C3H8 + 5O2 → 4H2O + 3CO2 + energy
Whether you consider cooking, souring, fermenting or burning, there is a chemical reaction accompanying these everyday processes. Thus, it won't be wrong to say learning chemistry and chemical reactions start at home.
By Ningthoujam Sandhyarani
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Text 5
Soy Biodiesel
Biofuels: Compared to petrodiesel emissions, biodiesel exhaust causes more inflammation in human cells and in mouse lungs
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Fueled By Soy
Vehicles that run on soy biodiesel emit less carbon monoxide and hydrocarbons than those that use petrodiesel. But the health effects of biodiesel emissions are still largely unknown.
Credit: Nebraska Soybean Board
Biodiesel, a fuel derived from animal or vegetable fats, is often touted as an environmentally friendly alternative to diesel made from petroleum. The fuel comes from a renewable resource, and burning it generates fewer greenhouse gases and less particulate matter than petrodiesel produces. However, very little is known about the health effects of biodiesel exhaust. Now a study finds that, compared to petrodiesel emissions, biodiesel exhaust may trigger greater inflammation in mammalian cells and lungs (Environ. Sci. Technol. 2013, DOI: 10.1021/es403146c).
In the U.S. and elsewhere, there is increasing interest in replacing or blending fossil fuels with renewable fuels like biodiesel, says Naomi K. Fukagawa of the University of Vermont. “Before going full steam ahead in shifting to new fuels, we should know the potential health consequences,” she says.
So Fukagawa and her colleagues collected exhaust particles from a Volkswagen light-duty diesel engine, fueled by either ultralow-sulfur petrodiesel or a certified soy-based biodiesel blend. The blend, known as B20, consisted of 20% biodiesel and 80% petrodiesel. B20 is commercially available and can be used in existing diesel vehicles without modifying the engines.
The team first analyzed the exhaust produced from both fuels using a scanning mobility particle sizer and thermal desorption/gas chromatography mass spectrometry. The petrodiesel generated two times as much particulate matter by mass as B20 did. However, the total surface area of B20-generated particles was twice as high as that for petrodiesel-generated particles because B20 combustion produced, on average, smaller particles. The chemical composition also differed between the two exhausts: Polar compounds made up 46% of the petrodiesel particles, compared to 68% for B20. The biodiesel-blend particles also contained short-chain fatty acid methyl esters, which are known lung irritants. These esters were absent from petrodiesel exhaust.
Next, the researchers exposed two human cell lines—macrophages and bronchial epithelial cells—to either petrodiesel or B20 exhaust particles for 24 hours. Cells treated with B20 particles released more proteins associated with inflammation than did those exposed to petrodiesel particles or untreated cells. For example, macrophages treated with B20 particles secreted about twice as much of the protein granulocyte colony-stimulating factor (G-CSF) as those treated with the same amount of petrodiesel particles by mass.
To test the effects of exhaust particles in living animals, Fukagawa and her colleagues aspirated a solution of the particles into the lungs of female mice once a day for three consecutive days. The researchers then euthanized the mice and collected tissue and fluid from their lungs. The concentrations of three inflammatory proteins—G-CSF, interleukin 6, and interferon-gamma-induced protein 10—were about two to three times higher in the lung tissue and fluid from B20-exposed mice than in animals exposed to petrodiesel particles. Persistent lung inflammation has been linked to diseases like chronic obstructive pulmonary disease, asthma, and lung cancer.
The inflammatory response caused by B20 particles may arise from some combination of the particles’ large surface area, their polar chemical composition, or the presence of short-chain fatty methyl esters, the researchers say. “Our findings do not mean that biodiesel is bad and should not be used,” Fukagawa says. “Rather, we need to know more about its components so we can design new engines or filters that will remove harmful components” in biodiesel exhaust.
Flemming R. Cassee of Utrecht University, in the Netherlands, says the researchers have added valuable data to the field’s limited knowledge of the health risks of biodiesel exhaust. However, he notes that the researchers tested only a fraction of the total exhaust: the particulate matter. Other components of the exhaust also could have health effects.
By Laura Cassiday
Литература
1. Texts 1-4. URL: http://www.buzzle.com/articles/chemistry
2. Text 5. URL: http://cen.acs.org/articles/91/web/2013/10/Soy-Biodiesel-Emissions-Trigger-Inflammation.html
3. Специфические особенности процесса обучения чтению. URL: http://student.zoomru.ru/ino/specificheskie-osobennosti-processa-obucheniya-chteniju/66727.540599.s2.html
4. Чтение. URL: http://ru.wikipedia.org/wiki/Чтение
5. Ломохова С.А. Самостоятельная работа студентов в процессе работы над текстом по специальности в неязыковом вузе. URL: http://cyberleninka.ru/article/n/samostoyatelnaya-rabota-studentov-v-protsesse-raboty-nad-tekstom-po-spetsialnosti-v-neyazykovom-vuze
