EV HSC Chemistry 2nd Paper 5th Chapter MCQ Question Answer
EV HSC Chemistry 2nd Paper 5th Chapter MCQ Question Answer. Economic Chemistry. Chemical marine pollution can cause many disturbances which, in the shorter or longer term, can have a negative impact on the economy. These effects may be related to living organisms, ecosystems as well as humans and their activities. The methods used to assess economic impact distinguish all that is of commercial value from all that is not. Resources of Resources can easily be calculated as they cover all that can be invoiced.
An example of this is a professional fishing ban due to the intoxication of fish flesh or due to a decrease in tourism in the incident area. Resources of non-commercial value are difficult to calculate as they cover all that cannot be invoiced. Some examples of this are a ban on recreational shellfish collection, sterility in certain mammals or damages caused to protected areas.
The other difficulty often encountered when assessing economic impact is the lack of relative data for the reference condition, i.e. before the pollution. For instance, in many countries, there is no water quality control network. The quantity of the substance normally present in the environment is unknown, making it impossible to compare this with the quantity found in the polluted water.
The amount is always expressed as a number of appropriate units. An acid-base titration is an example of quantitative analysis. In this module, you will learn about the core ideas or building blocks that are required for a deep understanding of quantitative chemistry. You will start to appreciate how relatively simple ideas develop and progress to more complex calculations as more knowledge is acquired. This line of progression is clearly seen in the thread of ideas, which may be used as a point of reference.
The study of organic reactions includes probing their scope through use in preparation of target compounds (e.g., natural products, drugs, polymers, etc.) by chemical synthesis, as well as the focused study of the reactivities of individual organic molecules, both in the laboratory and via theoretical (in silico) study.
Environmental chemistry is the study of chemical processes occurring in the environment which are impacted by humankind’s activities. These impacts may be felt on a local scale, through the presence of urban air pollutants or toxic substances arising from a chemical waste site, or on a global scale, through depletion of stratospheric ozone or global warming. The focus in our courses and research activities is upon developing a fundamental understanding of the nature of these chemical processes so that humankind’s activities can be accurately evaluated.
EV HSC Chemistry 2nd Paper 5th Chapter MCQ Question Answer. Economic Chemistry
Chemistry is one of the ancient and main disciplines of sciences. Various kinds of changes such as formation, destructions, growth, transformation, production etc. are discussed in chemistry. The practice of chemistry has been continuing for a number of millennia. The process of beautifying clothes by applying dyes was on track in the Indian subcontinent about 5000 years ago. Men started making metallic weapons, columns, and statues quite a long ago. In ancient times, precious metals like gold, silver, lead etc. were extracted from mines using chemical technologies.
Quantitative chemical analysis is a key part of environmental chemistry since it provides data that frame most environmental studies. Common analytical techniques used for quantitative determinations in environmental chemistry include classical wet chemistry, such as gravimetric, titrimetric and electrochemical methods. More sophisticated approaches are used in the determination of trace metals and organic compounds. Metals are commonly measured by atomic spectroscopy and mass spectrometry: Atomic Absorption Spectrophotometry (AAS) and Inductively Coupled Plasma Atomic Emission (ICP-AES) or Inductively Coupled Plasma Mass Spectrometric (ICP-MS) techniques.
Organic compounds are commonly measured also using mass spectrometric methods, such as Gas chromatography-mass spectrometry (GC/MS) and Liquid chromatography-mass spectrometry (LC/MS). Tandem Mass spectrometry MS/MS and High Resolution/Accurate Mass spectrometry HR/AM offer subpart per trillion detection. Non-MS methods using GCs and LCs having universal or specific detectors are still staples in the arsenal of available analytical tools
Other parameters often measured in environmental chemistry are radiochemicals. These are pollutants which emit radioactive materials, such as alpha and beta particles, posing danger to human health and the environment. Particle counters and Scintillation counters are most commonly used for these measurements. Bioassays and immunoassays are utilized for toxicity evaluations of chemical effects on various organisms. Polymerase Chain Reaction PCR is able to identify species of bacteria and other organisms through specific DNA and RNA gene isolation and amplification and are showing promise as a valuable technique for identifying environmental microbial contamination
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