Chemistry MCQs

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Acetic acid (CH3COOH) is a weak organic acid that gives vinegar its sour taste. At household concentrations (5-8% acetic acid), it is a mild acid. Vinegar can be made from a variety of base ingredients including wine, apple cider, rice, or malt. The acetic acid is produced by fermentation of the sugars in these ingredients. The most common type of vinegar in households is white distilled vinegar which is typically 4-7% acetic acid. It has a strong, pungent smell and flavor.

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Zinc sulfate is the inorganic compound with the formula ZnSO4 and historically known as “white vitriol” Zinc sulfate is an inorganic compound and dietary supplement.

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Cassiterite is a mineral that is primarily composed of tin dioxide (SnO2). It is the most important source of tin, and is also used as a semi-precious gemstone. Cassiterite is typically found in igneous and metamorphic rocks, and is often associated with other minerals such as quartz, feldspar, and mica. It has a high melting point and is resistant to weathering, making it a useful material for many industrial applications. The name “cassiterite” comes from the Greek word “kassiteros,” which means “tin.”

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Acid rain, or acid deposition, is a broad term that includes any form of precipitation with acidic components, such as sulphuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms.

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One of the most important chemical components of the troposphere is the ‘hydroxyl radical’: a highly reactive substance composed of an oxygen and a hydrogen atom, denoted ‘OH’. Hydroxyl radicals react with just about any other trace gas they encounter, removing them from the atmosphere.For example, OH combines with toxic carbon monoxide to generate carbon dioxide. In this sense, OH ‘cleans up’ the troposphere, and is sometimes called the detergent of the atmosphere.

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Plumbism is also known as lead poisoning or  a condition which occurs when there is accumulation of lead in body, usually over a few months' time period and even years.

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The most commonly recognised metalloids are boron, silicon, germanium, arsenic, antimony and tellurium. The other less recognised metalloids are: carbon, aluminium, selenium, polonium and astatine.Titanium is a lustrous transition metal with a silver color, low density and high strength.

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Of the alkaline earth metals calcium and magnesium rank fifth and sixth in abundance respectively in the earth’s crust. Strontium and barium have much lower abundances. Beryllium is rare and radium is the rarest of all comprising only 10^–10 per cent of igneous rocks.

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Alkynes contain at least one triple bond between two carbon atoms. The number of hydrogen atoms is less in alkynes as compared to alkenes or alkanes. Their general formula is C_nH_2n–2.

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The term pewter covers a variety of alloys consisting primarily of tin. It is composed of 85–99% tin, mixed with copper, antimony, bismuth, silver or lead..