Surface Chemistry & Solid State · JEE Main previous year questions

2019 14 questions

1. Q832019 · 12 Apr 2019 · Shift 1
   
   1. A.
   2. B.
   3. C.
   4. D.
   Show answer

   Answer: B

2. Q872019 · 12 Apr 2019 · Shift 1

   Peptization is a :

   1. A.process of converting soluble particles to form colloidal solution
   2. B.process of converting precipitate into colloidal solution
   3. C.process of bringing colloidal molecule into solution
   4. D.process of converting a colloidal solution into precipitate
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   Answer: B

3. Q892019 · 12 Apr 2019 · Shift 1

   An element has a face-centred cubic (fcc) structure with a cell edge of $a$. The distance between the centres of two nearest tetrahedral voids in the lattice is :

   1. A.$a$
   2. B.$\frac{3}{2}a$
   3. C.$\frac{a}{2}$
   4. D.$\sqrt{2}a$
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   Answer: C

4. Q832019 · 12 Apr 2019 · Shift 2

   Among the following, the INCORRECT statement about colloids is :

   1. A.The range of diameters of colloidal particles is between 1 and to 1000 nm
   2. B.they are larger than small molecules and have high molar mass
   3. C.They can scatter light
   4. D.The osmotic pressure of a colloidal solution is of higher order than the true solution at the same concentration.
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   Answer: D

5. Q872019 · 10 Apr 2019 · Shift 1

   A gas undergoes physical adsorption on a surface and follows the given Freundlich adsorption isotherm equation $\frac{x}{m}=k{p}^{0.5}$ Adsorption of the gas increase with :

   1. A.Decrease in p and increase in T
   2. B.Increase in p and decrease in T
   3. C.Decrease in p and decrease in T
   4. D.Increase in p and increase in T
   Show answer

   Answer: B

6. Q842019 · 9 Apr 2019 · Shift 1

   The aerosol is a kind of colloid in which :

   1. A.solid is dispersed in gas
   2. B.gas is dispersed in solid
   3. C.gas is dispersed in liquid
   4. D.liquid is dispersed in water
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   Answer: A

7. Q902019 · 9 Apr 2019 · Shift 1

   Match the catalysts (Column I) with products (Column II). $$\begin{array}{ll}\text{Column I}& \text{Column II}\\ \text{(A) }{\mathrm{V}}_2{\mathrm{O}}_5& \text{(i) Polyethylene}\\ \text{(B) }\mathrm{TiC}{\mathrm{l}}_4/Al(\mathrm{Me}{)}_3& \text{(ii) ethanal}\\ \text{(C) }\mathrm{PdC}{\mathrm{l}}_2& \text{(iii) }{\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4\\ \text{(D) Iron Oxide}& \text{(iv) }\mathrm{N}{\mathrm{H}}_3\end{array}$$

   1. A.(A)-(iii); (B)-(i); (C)-(ii); (D)-(iv)
   2. B.(A)-(ii); (B)-(iii); (C)-(i); (D)-(iv)
   3. C.(A)-(iii); (B)-(iv); (C)-(i); (D)-(ii)
   4. D.(A)-(iv); (B)-(iii); (C)-(ii); (D)-(i)
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   Answer: A

8. Q852019 · 9 Apr 2019 · Shift 2

   10 mL of 1mM surfactant solution forms a monolayer covering $0.24\mathrm{c}{\mathrm{m}}^2$ on a polar substrate. If the polar head is approximated as cube, what is its edge length?

   1. A.$1.0\mathrm{pm}$
   2. B.$2.0\mathrm{nm}$
   3. C.$0.1\mathrm{nm}$
   4. D.$2.0\mathrm{pm}$
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   Answer: D

9. Q882019 · 8 Apr 2019 · Shift 2

   Consider the bcc unit cells of the solids 1 and 2 with the position of atoms as shown below. The radius of atom B is twice that of atom A. The unit cell edge length is 50% more in solid 2 than in 1. What is the approximate packing efficiency in solid 2? [Figure: Solid 1 – bcc cell with atom A at all corners and at the body centre. Solid 2 – bcc cell with atom A at all corners and atom B at the body centre.]

   1. A.45%
   2. B.90%
   3. C.75%
   4. D.65%
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   Answer: B

10. Q742019 · 11 Jan 2019 · Shift 2

    The coordination number of Th in ${\mathrm{K}}_4[\mathrm{Th}({\mathrm{C}}_2{\mathrm{O}}_4{)}_4(\mathrm{O}{\mathrm{H}}_2{)}_2]$ is : $({\mathrm{C}}_2{\mathrm{O}}_4^{2-}=\text{Oxalato})$

    1. A.14
    2. B.10
    3. C.8
    4. D.6
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    Answer: B

11. Q812019 · 11 Jan 2019 · Shift 2

    The radius of the largest sphere which fits properly at the centre of the edge of a body centred cubic unit cell is : (Edge length is represented by 'a')

    1. A.0.134 a
    2. B.0.067 a
    3. C.0.047 a
    4. D.0.027 a
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    Answer: B

12. Q862019 · 11 Jan 2019 · Shift 2

    Among the colloids cheese (C), milk (M), and smoke (S), the correct combination of the dispersed phase and dispersion medium, respectively is :

    1. A.C : liquid in solid ; M : liquid in liquid ; S : solid in gas
    2. B.C : liquid in solid ; M : liquid in solid ; S : solid in gas
    3. C.C : solid in liquid ; M : liquid in liquid ; S : gas in solid
    4. D.C : solid in liqid ; M : solid in liquid ; S : solid in gas
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    Answer: A

13. Q852019 · 9 Jan 2019 · Shift 1

    The alkaline earth metal nitrate that does not crystallise with water molecules, is :

    1. A.$\mathrm{Mg}(\mathrm{N}{\mathrm{O}}_3{)}_2$
    2. B.$\mathrm{Sr}(\mathrm{N}{\mathrm{O}}_3{)}_2$
    3. C.$\mathrm{Ca}(\mathrm{N}{\mathrm{O}}_3{)}_2$
    4. D.$\mathrm{Ba}(\mathrm{N}{\mathrm{O}}_3{)}_2$
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    Answer: D

14. Q902019 · 9 Jan 2019 · Shift 1
    
    1. A.${\mathrm{P}}^2$
    2. B.${\mathrm{P}}^{\frac{1}{4}}$
    3. C.${\mathrm{P}}^{\frac{1}{2}}$
    4. D.$\mathrm{P}$
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    Answer: C