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2024 85 questions

1. Q642024 · 9 Apr 2024 · Shift 1
   
   1. A.Molarity of ${\mathrm{K}}_2\mathrm{C}{\mathrm{r}}_2{\mathrm{O}}_7$ solution is lowered.
   2. B.Green colour formation observed on side Y.
   3. C.Molarity of $\mathrm{CuS}{\mathrm{O}}_4$ solution is lowered.
   4. D.Green colour formation observed on side X.
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   Answer: C

2. Q662024 · 9 Apr 2024 · Shift 1

   The ${\mathrm{F}}^{-}$ ions make the enamel on teeth much harder by converting hydroxyapatite (the enamel on the surface of teeth) into much harder fluoroapatite having the formula.

   1. A.$[3(\mathrm{C}{\mathrm{a}}_3(\mathrm{P}{\mathrm{O}}_4{)}_2)\cdot \mathrm{Ca}{\mathrm{F}}_2]$
   2. B.$[3(\mathrm{C}{\mathrm{a}}_3(\mathrm{P}{\mathrm{O}}_4{)}_2)\cdot \mathrm{Ca}(\mathrm{OH}{)}_2]$
   3. C.$[3(\mathrm{C}{\mathrm{a}}_3(\mathrm{P}{\mathrm{O}}_4{)}_3)\cdot \mathrm{Ca}{\mathrm{F}}_2]$
   4. D.$[3(\mathrm{C}{\mathrm{a}}_2(\mathrm{P}{\mathrm{O}}_4{)}_2)\cdot \mathrm{Ca}(\mathrm{OH}{)}_2]$
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   Answer: A

3. Q682024 · 9 Apr 2024 · Shift 1
   
   1. A.
   2. B.
   3. C.
   4. D.
   Show answer

   Answer: A

4. Q732024 · 9 Apr 2024 · Shift 1
   
   1. A.(E) < (D) < (C) < (B) < (A)
   2. B.(B) < (D) < (A) < (C) < (E)
   3. C.(D) < (E) < (C) < (B) < (A)
   4. D.(E) < (D) < (B) < (A) < (C)
   Show answer

   Answer: B

5. Q852024 · 9 Apr 2024 · Shift 1· Numerical answer

   The total number of species from the following in which one unpaired electron is present, is ____. ${\mathrm{N}}_2,{\mathrm{O}}_2,{\mathrm{C}}_2^{-},{\mathrm{O}}_2^{-},{\mathrm{O}}_2^{2-},{\mathrm{H}}_2^{+},\mathrm{C}{\mathrm{N}}^{-},\mathrm{H}{\mathrm{e}}_2^{+}$

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   Answer: 4

6. Q882024 · 9 Apr 2024 · Shift 1· Numerical answer

   When equal volume of $1\mathrm{M}\mathrm{HCl}$ and $1\mathrm{M}{\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4$ are separately neutralised by excess volume of $1\mathrm{M}\mathrm{NaOH}$ solution. $x$ and $y\mathrm{kJ}$ of heat is liberated respectively. The value of $y/x$ is ____.

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   Answer: 2

7. Q892024 · 9 Apr 2024 · Shift 1· Numerical answer

   The heat of solution of anhydrous $\mathrm{CuS}{\mathrm{O}}_4$ and $\mathrm{CuS}{\mathrm{O}}_4\cdot 5{\mathrm{H}}_2\mathrm{O}$ are $-70\mathrm{kJ}\mathrm{mo}{\mathrm{l}}^{-1}$ and $+12\mathrm{kJ}\mathrm{mo}{\mathrm{l}}^{-1}$ respectively. The heat of hydration of $\mathrm{CuS}{\mathrm{O}}_4$ to $\mathrm{CuS}{\mathrm{O}}_4\cdot 5{\mathrm{H}}_2\mathrm{O}$ is $-x\mathrm{kJ}$. The value of $x$ is ____. (nearest integer).

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   Answer: 82

8. Q702024 · 9 Apr 2024 · Shift 2

   The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency '$A$' $\times 10^{12}\mathrm{hertz}$ and that has a radiant intensity in that direction of $\frac{1}{\prime B^{\prime }}$, watt per steradian. '$A$' and '$B$' are respectively

   1. A.450 and 683
   2. B.540 and $\frac{1}{683}$
   3. C.540 and 683
   4. D.450 and $\frac{1}{683}$
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   Answer: C

9. Q872024 · 9 Apr 2024 · Shift 2· Numerical answer

   When $\Delta {\mathrm{H}}_{\mathrm{vap}}=30kJ/mol$ and $\Delta {\mathrm{S}}_{\mathrm{vap}}=75\mathrm{J}\mathrm{mo}{\mathrm{l}}^{-1}{\mathrm{K}}^{-1}$, then the temperature of vapour, at one atmosphere is ____ K.

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   Answer: 400

10. Q742024 · 8 Apr 2024 · Shift 1
    
    1. A.Two
    2. B.Three
    3. C.Four
    4. D.One
    Show answer

    Answer: D

11. Q792024 · 8 Apr 2024 · Shift 1
    
    1. A.can be oxidized to a dicarboxylic acid with $\mathrm{B}{\mathrm{r}}_2$ water
    2. B.despite the presence of $-\mathrm{CHO}$ does not give Schiff's test
    3. C.will coexist in equilibrium with 2 other cyclic structures
    4. D.has 4 asymmetric carbon atoms
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    Answer: A

12. Q842024 · 8 Apr 2024 · Shift 1· Numerical answer
    
    Show answer

    Answer: 5

13. Q872024 · 8 Apr 2024 · Shift 1· Numerical answer

    Number of molecules from the following which are exceptions to octet rule is ____. $\mathrm{C}{\mathrm{O}}_2,\mathrm{N}{\mathrm{O}}_2,{\mathrm{H}}_2\mathrm{S}{\mathrm{O}}_4,\mathrm{B}{\mathrm{F}}_3,\mathrm{C}{\mathrm{H}}_4,\mathrm{Si}{\mathrm{F}}_4,\mathrm{Cl}{\mathrm{O}}_2,\mathrm{PC}{\mathrm{l}}_5,\mathrm{Be}{\mathrm{F}}_2,{\mathrm{C}}_2{\mathrm{H}}_6,\mathrm{CHC}{\mathrm{l}}_3,\mathrm{CB}{\mathrm{r}}_4$

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    Answer: 6

14. Q612024 · 8 Apr 2024 · Shift 2
    
    1. A.(A)-(II), (B)-(IV), (C)-(I), (D)-(III)
    2. B.(A)-(I), (B)-(IV), (C)-(II), (D)-(III)
    3. C.(A)-(III), (B)-(II), (C)-(I), (D)-(IV)
    4. D.(A)-(IV), (B)-(II), (C)-(III), (D)-(I)
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    Answer: A

15. Q652024 · 8 Apr 2024 · Shift 2

    Which one of the following compounds will readily react with dilute $\mathrm{NaOH}$ ?

    1. A.${\mathrm{C}}_6{\mathrm{H}}_5\mathrm{C}{\mathrm{H}}_2\mathrm{OH}$
    2. B.${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$
    3. C.${\mathrm{C}}_6{\mathrm{H}}_5\mathrm{OH}$
    4. D.$(\mathrm{C}{\mathrm{H}}_3{)}_3\mathrm{COH}$
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    Answer: C

16. Q682024 · 8 Apr 2024 · Shift 2

    The emf of cell $\mathrm{Tl}\left|\underset{(0.001\mathrm{M})}{\mathrm{T}{\mathrm{l}}^{+}}\right|\left|\underset{(0.01\mathrm{M})}{\mathrm{C}{\mathrm{u}}^{2+}}\right|\mathrm{Cu}$ is $0.83\mathrm{V}$ at $298\mathrm{K}$. It could be increased by :

    1. A.increasing concentration of $\mathrm{T}{\mathrm{l}}^{+}$ ions
    2. B.increasing concentration of $\mathrm{C}{\mathrm{u}}^{2+}$ ions
    3. C.increasing concentration of both $\mathrm{T}{\mathrm{l}}^{+}$ and $\mathrm{C}{\mathrm{u}}^{2+}$ ions
    4. D.decreasing concentration of both $\mathrm{T}{\mathrm{l}}^{+}$ and $\mathrm{C}{\mathrm{u}}^{2+}$ ions
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    Answer: B

17. Q702024 · 8 Apr 2024 · Shift 2

    The correct sequence of acidic strength of the following aliphatic acids in their decreasing order is: $\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{COOH},\mathrm{C}{\mathrm{H}}_3\mathrm{COOH},\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{COOH},\mathrm{HCOOH}$

    1. A.$\mathrm{HCOOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{COOH}$
    2. B.$\mathrm{HCOOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}$
    3. C.$\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{COOH}>\mathrm{HCOOH}$
    4. D.$\mathrm{C}{\mathrm{H}}_3\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}>\mathrm{C}{\mathrm{H}}_3\mathrm{C}{\mathrm{H}}_2\mathrm{C}{\mathrm{H}}_2\mathrm{COOH}>\mathrm{HCOOH}$
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    Answer: B

18. Q712024 · 8 Apr 2024 · Shift 2

    For a reaction $A\stackrel{{\mathrm{K}}_1}{\to }\mathrm{B}\stackrel{{\mathrm{K}}_2}{\to }\mathrm{C}$ If the rate of formation of $\mathrm{B}$ is set to be zero then the concentration of $\mathrm{B}$ is given by :

    1. A.$({\mathrm{K}}_1-{\mathrm{K}}_2)[\mathrm{A}]$
    2. B.$({\mathrm{K}}_1+{\mathrm{K}}_2)[\mathrm{A}]$
    3. C.${\mathrm{K}}_1{\mathrm{K}}_2[\mathrm{A}]$
    4. D.$({\mathrm{K}}_1/{\mathrm{K}}_2)[\mathrm{A}]$
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    Answer: D

19. Q892024 · 8 Apr 2024 · Shift 2· Numerical answer

    Wavenumber for a radiation having $5800\text{ A˚}$ wavelength is $x\times 10{\text{ cm}}^{-1}$. The value of $x$ is ______. (Integer answer)

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    Answer: 1724

20. Q742024 · 6 Apr 2024 · Shift 2

    Arrange the following elements in the increasing order of number of unpaired electrons in it. (A) $\text{Sc}$ (B) $\text{Cr}$ (C) $\text{V}$ (D) $\text{Ti}$ (E) $\text{Mn}$ Choose the correct answer from the options given below :

    1. A.(A) < (D) < (C) < (B) < (E)
    2. B.(A) < (D) < (C) < (E) < (B)
    3. C.(B) < (C) < (D) < (E) < (A)
    4. D.(C) < (E) < (B) < (A) < (D)
    Show answer

    Answer: B

21. Q772024 · 6 Apr 2024 · Shift 2

    The ratio $\frac{K_p}{K_c}$ for the reaction : ${\text{CO}}_{(g)}+\frac{1}{2}{\text{O}}_{2(g)}\rightleftharpoons {\text{CO}}_{2(g)}$ is :

    1. A.$1$
    2. B.$(\text{RT}{)}^{1/2}$
    3. C.$\text{RT}$
    4. D.$\frac{1}{\sqrt{\text{RT}}}$
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    Answer: D

22. Q852024 · 6 Apr 2024 · Shift 2· Numerical answer

    For hydrogen atom, energy of an electron in first excited state is $-3.4\text{ eV}$. K.E. of the same electron of hydrogen atom is $x\text{ eV}$. Value of $x$ is ________ $\times 10^{-1}\text{ eV}$. (Nearest integer)

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    Answer: 34

23. Q622024 · 5 Apr 2024 · Shift 2

    Match List I with List II. $$\begin{array}{llll}& \text{LIST I}& & \text{LIST II}\\ \text{A.}& \mathrm{ICl}& \text{I.}& \text{T - shape}\\ \text{B.}& \mathrm{IC}{\mathrm{l}}_3& \text{II.}& \text{Square pyramidal}\\ \text{C.}& \mathrm{Cl}{\mathrm{F}}_5& \text{III.}& \text{Pentagonal bipyramidal}\\ \text{D.}& \mathrm{I}{\mathrm{F}}_7& \text{IV.}& \text{Linear}\end{array}$$ Choose the correct answer from the options given below :

    1. A.(A)-(I), (B)-(IV), (C)-(III), (D)-(II)
    2. B.(A)-(IV), (B)-(I), (C)-(II), (D)-(III)
    3. C.(A)-(I), (B)-(III), (C)-(II), (D)-(IV)
    4. D.(A)-(IV), (B)-(III), (C)-(II), (D)-(I)
    Show answer

    Answer: B

24. Q632024 · 5 Apr 2024 · Shift 2
    
    1. A.2-carboxy-4-hydroxyhept-7-enal
    2. B.2-formyl-4-hydroxyhept-7-enoic acid
    3. C.2-carboxy-4-hydroxyhept-6-enal
    4. D.2-formyl-4-hydroxyhept-6-enoic acid
    Show answer

    Answer: D

25. Q702024 · 5 Apr 2024 · Shift 2
    
    1. A.picric acid
    2. B.oxalic acid
    3. C.adipic acid
    4. D.acetic acid
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    Answer: C