Surface Chemistry & Solid State · JEE Advanced previous year questions

2025 2 questions

1. Q412025 · 18 May 2025 · Paper 2· Numerical answer

   The density (in $\mathrm{g}\mathrm{c}{\mathrm{m}}^{-3}$) of the metal which forms a cubic close packed (ccp) lattice with an axial distance (edge length) equal to $400\text{ pm}$ is _________. $\text{Use:}$ Atomic mass of metal $=105.6\text{ amu}$ and Avogadro's constant $=6\times 10^{23}{\text{ mol}}^{-1}$

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   Answer: 10.85 to 11.1

2. Q432025 · 18 May 2025 · Paper 2· Numerical answer

   Adsorption of phenol from its aqueous solution on to fly ash obeys Freundlich isotherm. At a given temperature, from $10{\text{ mg g}}^{-1}$ and $16{\text{ mg g}}^{-1}$ aqueous phenol solutions, the concentrations of adsorbed phenol are measured to be $4{\text{ mg g}}^{-1}$ and $10{\text{ mg g}}^{-1}$, respectively. At this temperature, the concentration (in ${\text{mg g}}^{-1}$) of adsorbed phenol from $20{\text{ mg g}}^{-1}$ aqueous solution of phenol will be _________. $\text{Use:}$ ${\log }_{10}2=0.3$

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   Answer: 15.5 to 16.5