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The student was unable to close the pinch clamp completely,prior to transferring the flask from the...

The student was unable to close the pinch clamp completely,prior to transferring the flask from the boiling water to the cold water bath
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Answer #1

Ans. NOT closing the pinch clamp properly may have following effects-

I. While flask is cooled, the vapor condensed leading to reduction in the volume of vapor in flask. It creates a negative pressure. If the pinch clamp in NOT closed people, the negative pressure in flask would lead to inward suction of air.

II. Inward suction of air into flask would increase the mass of flask. It would thus give the abnormally high mass of the vapor present in the flask.

III. “Molar mass = Mass of vapor / n” . Since “mass of vapor” is abnormally high, the resultant molar mass of the compound/substance would be higher than the actual value.

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