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Is Matter Around Us Pure — Science STD 9 — Question

Gujarat BoardEnglish MediumSTD 9ScienceIs Matter Around Us Pure4 Marks
Question
The liquid air has three components $X , Y$ and $Z$ whose boiling points are: $-186^{\circ} C ,-183^{\circ} C$ and $-196^{\circ} C$, respectively. When liquid air is fed into a tall fractional distillation column from near its bottom and warmed up slowly:
a. Which component will be collected from near the bottom of the fraction distillation column? Why?
b. Which component will be collected from the top part of the fractional distillation column? Why?
c. Which component will be collected from the middle part of the fractional distillation column? Why?
d. What could the component $X , Y$ and $Z$ be?
✓

Answer

a. $Y$ will be collected from the area near the bottom of the fractional distillation column because it has highest boiling point $\left(-183^{\circ} C \right)$.
b. $Z$ will be collected from the top part of the fractional distillation column because it has lowest boiling point $\left(-196^{\circ} C \right)$.
c. $X$ will be collected from the middle part of the fractional distillation column because it has a boiling point $-186^{\circ} C$, which is lower than that of $Y$ but higher than that of $Z .$
d. $X$ is liquid argon,$ Y$ is liquid oxygen, and $Z$ is liquid nitrogen.

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