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Acid Rain
Published in Mary K. Theodore, Louis Theodore, Introduction to Environmental Management, 2021
Mary K. Theodore, Louis Theodore
Acid rain with a pH below 5.6 is formed when certain anthropogenic air pollutants travel into the atmosphere and react with moisture and sunlight to produce acidic compounds. Sulfur and nitrogen compounds released into the atmosphere from different sources are believed to play the biggest role in the formation of acid rain. The natural processes that contribute to acid rain include lightning, ocean spray, decaying plant and bacterial activity in the soil, and volcanic eruptions. Anthropogenic sources include those utilities, industries, businesses, and homes that burn fossils fuels, plus motor vehicle emission. Sulfuric acid is the type of acid most commonly formed in areas that burn coal for electricity, while nitric acid is more common in areas that have a high density of automobiles and other internal combustion engines.
Basic Chemical Principles
Published in John A. Conkling, Christopher J. Mocella, Chemistry of Pyrotechnics, 2019
John A. Conkling, Christopher J. Mocella
There are several concepts and theories for acid–base reactions but the one most useful in pyrotechnics is Brønsted–Lowry acid–base theory, named after the scientists who independently developed the model. In this concept, an acid is commonly described as a molecule or ion that can serve as a hydrogen ion (H+) donor. The hydrogen ion is identical to the proton—it contains one proton in the nucleus and has no electrons surrounding the nucleus. H+ is a light, mobile, reactive species. A base is a species that functions as a hydrogen ion acceptor, such as a hydroxide ion, OH−. The transfer of a hydrogen ion (proton) from a good donor to a good acceptor is called an acid–base reaction. Materials that are neither acidic nor basic in nature are said to be neutral, while those that can act as both an acid and a base (such as water) are called amphoteric.
Fundamentals of Electric Capacitors
Published in Aiping Yu, Victor Chabot, Jiujun Zhang, Electrochemical Supercapacitors for Energy Storage and Delivery, 2017
Aiping Yu, Victor Chabot, Jiujun Zhang
A typical non-aqueous-based liquid electrolyte is generally composed of a weak acid, a salt derived from a weak acid, a solvent, an optional thickening agent, and other additives. The electrolyte is usually soaked into an electrode separator that serves as the dielectric. Weak acids are organic and include glacial acetic acid, lactic acid, propionic acid, butyric acid, crotonic acid, acrylic acid, phenol, and cresol. The salts are ammonium or metal salts of organic acids, including ammonium acetate, ammonium citrate, aluminum acetate, calcium lactate, and ammonium oxalate; or weak inorganic acids such as sodium perborate and trisodium phosphate. Electrolyte solvents are based on alkanolamines (monoethanolamine, diethanolamine, and triethanolamine) or polyols (diethylene glycol, and glycerol).
Water quality assessment of Mansbal Lake in Kashmir
Published in Water Science, 2022
Daawar Bashir Ganaie, Anirudh Malhotra, Irfan Ahmad Wani
pH (power of hydrogen/ hydrogen ion activity or concentration) scale is used to analyze the acidity or basicity of a given solution/liquid. The scale measures the values from 1 to 15, values being below 7 pH are categorized as acidic, while above 7 pH as basic and 7 pH denotes as neutral. Hydrogen ion concentration (pH) is well defined as the decimal logarithm of the reciprocal of the hydrogen ion activity (Covington, Bates, & Durst, 1985). pH that maintains the acidic or basic property, is a vital characteristic of any aquatic ecosystem since all the biochemical activities and retention of physicochemical attributes of the water are greatly dependent on the pH of the surrounding water (Jalal & Sanal Kumar, 2013). In the present study, the pH values ranged between 8.9 pH and 7.6 pH showing alkaline nature of water, indicating the lake was well buffered during this period of study. The highest pH values in all the months were recorded at Kondabal site 2 because of the calcium intrusion and heavy pollution load from the near catchment area. This inconstancy in pH values can be attributed to the influence of the variations in photosynthetic and decomposition rates of organic matter due to high pollution, and this statement also goes well with the findings of (Shah, Pandit, & Shah, 2017).
Artificial aging test method for the assessment of changes in properties of architectural membranes and membrane connections
Published in The Journal of The Textile Institute, 2023
Loreta Šveikauskaitė, Vaida Dobilaitė, Milda Jucienė
When the effect of precipitation is simulated under artificial aging conditions, acidic rains are considered to be more harmful because they accelerate the aging of polymer-coated materials. Acidic rains are caused by emissions of sulphur and nitrogen compounds into the atmosphere. Due to exposure to solar radiation and chemical impurities in the air and moisture, these hazardous substances turn into sulphuric and nitrogen acids. In order to simulate the effect of acid rain, it is planned to soak the specimens in water with pH = 4.5. According to standards (ISO 9142:2003, ISO 175:2010) and artificial aging methodologies used by other scientists (Asadi et al., 2018; Asadi, 2021b) to simulate the impact of rain, the specimens are immersed 5 times for 24 h.
Fabrication of spirulina based activated carbons for wastewater treatment
Published in Environmental Technology, 2022
Mustafa Rakib, Yeshaswini Baddam, Balakrishnan Subeshan, Ayse B. Sengul, Eylem Asmatulu
pH is the measurement of the acidity or alkalinity of water. This measure determines the concentration of hydrogen ion [H+] and can be expressed mathematically as pH = –log [H+]. The pH scale can calculate values from 0 to 14, where 0 means a highly concentrated strong acid, 14 means a highly concentrated base, and 7 is the neutral pH. Pure water should have a pH of 7 [70]. In 1984, new pH guidelines for drinking water were introduced, and the new range was between 6.5 and 8.5. Until now, this range was considered the usual pH range. Sometimes the ideal pH range for drinking water is recommended between 6.5 and 9.5 [71].