Water has a vapor pressure at 100°C equal to___________________?
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Answer: B. 760 mm Hg
Explanation
Boiling occurs when a liquid vapor pressure equals surrounding atmospheric pressure. Standard atmospheric pressure at sea level equals exactly 760 mm Hg. Water boils at 100 degrees Celsius under this standard pressure condition. Vapor pressure increases as liquid temperature rises toward the boiling point. Standard pressure is defined as one atmosphere or 760 mm Hg. Phase change equilibria dictate boiling point temperatures for pure substances.
Cooking food at high altitudes takes longer due to lower atmospheric pressure. Industrial distillation columns operate by controlling internal vapor pressures. Weather forecasting tracks barometric pressure changes using mm Hg units. Option A is incorrect because 55 mm Hg corresponds to a much lower temperature. Option C is incorrect because 355 mm Hg occurs below the boiling point. Option D is incorrect because 1489 mm Hg requires elevated boiling temperatures.
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Answer: C. Nascent oxygen[O]
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Q2. Lipids exhibit solubility in___________________?
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Answer: A. Organic solvents
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Q3. Hydrogen bonding plays a crucial role in____________________?
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Answer: D. All
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Q4. When a substance transitions from solid to liquid, all of the following changes take place except__________________?
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Answer: B. K.E of the molecules decreases
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Q5. To elevate the boiling point of water to 110°C, what external pressure is required?
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Answer: A. Between 760 torr and 1200 torr
Higher boiling points require increased external vapor pressure on liquids. Elevating water boiling to 110 degrees Celsius demands higher pressure environments. Pressure cooker devices use this principle to cook food fas...
Q6. A table of elements referenced against a hydrogen scale is known as________________?
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Answer: D. electrochemical series
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