Gooch crucibles are manufactured from________________?
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Answer: C. porcelain
Explanation
Gooch crucibles feature a perforated bottom designed to support a filter mat for analytical gravimetry. Porcelain is chosen for manufacturing Gooch crucibles because it withstands extreme ignition temperatures. Analytical porcelain ware resists chemical attack and thermal shock during high-temperature crucible drying. Gravimetric analysis requires crucibles that can be heated to constant weight in high-temperature muffle furnaces. Porcelain is a vitrified ceramic material known for its hardness, chemical inertness, and thermal stability. Filtering crucibles allow precipitates to be collected, dried, and weighed accurately in analytical labs.
Quantitative chemical analysis laboratories rely on porcelain Gooch crucibles for precise mass determinations. Analytical chemists heat crucibles repeatedly to ensure no volatile impurities remain before sample weighing. Selecting appropriate laboratory glassware and ceramics prevents contamination during precise analytical assays. Plastic crucibles would melt or decompose instantly under the high ignition temperatures required. Fibre materials lack the necessary heat resistance to survive ignition inside analytical muffle furnaces. Steel crucibles would oxidize and corrode during prolonged high-temperature heating in air atmospheres.
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