In Dumas' method for estimation of nitrogen, 1mathrm~g$1\mathrm{~g}$ of an organic compound gave 150mathrm~mL$150\mathrm{~mL}$ of nitrogen collected at 300mathrm~K$300\mathrm{~K}$ temperature and 900mathrm~mmHg$900\mathrm{~mmHg}$ pressure. The percentage composition of nitrogen in the compound is _______ %$%$ (nearest integer). (Aqueous tension at 300mathrm~K = 15mathrm~mmHg$300\mathrm{~K} = 15\mathrm{~mmHg}$)

### Core Logic The fundamental principle used in chromatography (such as column chromatography or thin-layer chromatography) is adsorption. Different components of a mixture are adsorbed to different extents on an adsorbent stationary phase. ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Chemistry: Organic Chemistry - Some Basic Principles and Techniques

### Core Logic (A) Simple distillation is used to separate a mixture of miscible liquids with a sufficiently large difference in their boiling points, such as chloroform and aniline. (A rightarrow$\rightarrow$ IV) (B) Fractional distillation is used to separate crude oil fractions. (B rightarrow$\rightarrow$ III) (C) Steam distillation is used to separate steam-volatile substances that are immiscible with water, like an aniline-water mixture. (C rightarrow$\rightarrow$ II) (D) Distillation under reduced pressure is used for liquids that decompose at or below their normal boiling points, like separating glycerol from spent lye. (D rightarrow$\rightarrow$ I) ### Evaluation Rubric / Model Answer null ### Chapter Mix Class 11 Chemistry: Organic Chemistry - Some Basic Principles and Techniques