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2023 96 questions

Q782023 · 31 Jan 2023 · Shift 2
Which of the following compounds are not used as disinfectants ? A. Chloroxylenol B. Bithional C. Veronal D. Prontosil E. Terpineol Choose the correct answer from the options given below :
1. A.A, B
2. B.C, D
3. C.B, D, E
4. D.A, B, E
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Answer: B
Q802023 · 31 Jan 2023 · Shift 2
Which one of the following statements is incorrect?
1. A.Cast iron is obtained by melting pig iron with scrap iron and coke using hot air blast.
2. B.The malleable iron is prepared from cast iron by oxidising impurities in a reverberatory furnace.
3. C.van Arkel method is used to purify tungsten.
4. D.Boron and Indium can be purified by zone refining method.
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Answer: C
Q822023 · 31 Jan 2023 · Shift 2· Numerical answer
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Answer: 3
Q652023 · 30 Jan 2023 · Shift 1
1. A. $H_{D} > H_{C} > H_{B} > H_{A}$
2. B. $H_{C} > H_{A} > H_{D} > H_{B}$
3. C. $H_{C} > H_{D} > H_{B} > H_{A}$
4. D. $H_{C} > H_{D} > H_{A} > H_{B}$
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Answer: D
Q742023 · 30 Jan 2023 · Shift 1
Caprolactam when heated at high temperature in presence of water, gives
1. A.Dacron
2. B.Nylon 6
3. C.Teflon
4. D.Nylon 6,6
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Answer: B
Q882023 · 30 Jan 2023 · Shift 1· Numerical answer
A solution containing $2 g$ of a non-volatile solute in $20 g$ of water boils at $373.52 K$ . The molecular mass of the solute is ___________ $g mol^{- 1}$ . (Nearest integer) Given, water boils at $373 K$ , $K_{b}$ for water $= 0.52 K kg mol^{- 1}$
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Answer: 100
Q622023 · 29 Jan 2023 · Shift 1
The magnetic behaviour of $L i_{2} O, N a_{2} O_{2}$ and $K O_{2}$ , respectively, are :
1. A.paramagnetic, paramagnetic and diamagnetic
2. B.paramagnetic, diamagnetic and paramagnetic
3. C.diamagnetic, paramagnetic and diamagnetic
4. D.diamagnetic, diamagnetic and paramagnetic
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Answer: D
Q672023 · 29 Jan 2023 · Shift 1
The shortest wavelength of hydrogen atom in Lyman series is $λ$ . The longest wavelength in Balmer series of $H e^{+}$ is
1. A. $\frac{36 λ}{5}$
2. B. $\frac{5}{9 λ}$
3. C. $\frac{9 λ}{5}$
4. D. $\frac{5 λ}{9}$
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Answer: C
Q732023 · 29 Jan 2023 · Shift 1
The correct order of hydration enthalpies is (A) $K^{+}$ (B) $R b^{+}$ (C) $M g^{2 +}$ (D) $C s^{+}$ (E) $C a^{2 +}$ Choose the correct answer from the options given below :
1. A.E > C > A > B > D
2. B.C > A > E > B > D
3. C.C > E > A > D > B
4. D.C > E > A > B > D
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Answer: D
Q762023 · 29 Jan 2023 · Shift 1
Which of the given compounds can enhance the efficiency of hydrogen storage tank?
1. A. $Si H_{4}$
2. B. $Li/ P_{4}$
3. C. $NaN i_{5}$
4. D.Di-isobutylaluminium hydride
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Answer: C
Q842023 · 29 Jan 2023 · Shift 1· Numerical answer
The number of molecules or ions from the following, which do not have odd number of electrons are ____. (A) $N O_{2}$ (B) $IC l_{4}^{-}$ (C) $Br F_{3}$ (D) $Cl O_{2}$ (E) $N O_{2}^{+}$ (F) NO
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Answer: 3
Q632023 · 29 Jan 2023 · Shift 2
Which of the following relations are correct? (A) $Δ U = q + p Δ V$ (B) $Δ G = Δ H - T Δ S$ (C) $Δ S = \frac{q _{rev}}{T}$ (D) $Δ H = Δ U - Δ n RT$ Choose the most appropriate answer from the options given below :
1. A.A and B only
2. B.B and C only
3. C.C and D only
4. D.B and D only
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Answer: B
Q902023 · 29 Jan 2023 · Shift 2· Numerical answer
On heating, $LiN O_{3}$ gives how many compounds among the following ____ $L i_{2} O, N_{2}, O_{2}, LiN O_{2}, N O_{2}$
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Answer: 3
Q642023 · 25 Jan 2023 · Shift 1
1. A.A $\to$ iii, B $\to$ iv, C $\to$ i, D $\to$ ii
2. B.A $\to$ iv, B $\to$ iii, C $\to$ i, D $\to$ ii
3. C.A $\to$ i, B $\to$ ii, C $\to$ iii, D $\to$ iv
4. D.A $\to$ iii, B $\to$ iv, C $\to$ ii, D $\to$ i
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Answer: A
Q662023 · 25 Jan 2023 · Shift 1
Match List I with List II $A. B. C. D. List I Elements K Ca Sr Ba I. II. III. IV. List II Colour imparted to the flame Brick Red Violet Apple Green Crimson Red$ Choose the correct answer from the options given below :
1. A.A-II, B-IV, C-I, D-III
2. B.A-II, B-I, C-IV, D-III
3. C.A-II, B-I, C-III, D-IV
4. D.A-IV, B-III, C-II, D-I
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Answer: B
Q692023 · 25 Jan 2023 · Shift 1
The radius of the $2^{nd}$ orbit of $L i^{2 +}$ is $x$ . The expected radius of the $3^{rd}$ orbit of $B e^{3 +}$ is
1. A. $\frac{16}{27} x$
2. B. $\frac{4}{9} x$
3. C. $\frac{9}{4} x$
4. D. $\frac{27}{16} x$
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Answer: D
Q712023 · 25 Jan 2023 · Shift 1
Given below are two statements : one is labelled as Assertion A and the other is labelled as Reason R : Assertion A : Acetal / Ketal is stable in basic medium. Reason R : The high leaving tendency of alkoxide ion gives the stability to acetal/ketal in basic medium. In the light of the above statements, choose the correct answer from the options given below :
1. A.A is false but R is true.
2. B.Both A and R are true but R is NOT the correct explanation of A
3. C.Both A and R are true and R is the correct explanation of A
4. D.A is true but R is false.
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Answer: D
Q812023 · 25 Jan 2023 · Shift 1· Numerical answer
The density of a monobasic strong acid (Molar mass 24.2 g/mol) is 1.21 kg/L. The volume of its solution required for the complete neutralization of 25 mL of 0.24 M NaOH is ____ $\times 1 0^{- 2}$ mL (Nearest integer)
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Answer: 12
Q832023 · 25 Jan 2023 · Shift 1· Numerical answer
Consider the cell $Pt (s) ∣ H_{2} (g) (1 atm) ∣ H^{+} (aq, [H^{+}] = 1) ∣∣F e^{3 +} (aq), F e^{2 +} (aq) ∣Pt (s)$ Given $E_{F e^{3 +} /F e^{2 +}}^{o} = 0.771 V$ and $E_{H^{+} /1/2 H_{2}}^{o} = 0 V$ , $T = 298 K$ If the potential of the cell is 0.712 V, the ratio of concentration of $F e^{2 +}$ to $F e^{3 +}$ is ____ (Nearest integer)
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Answer: 10
Q612023 · 25 Jan 2023 · Shift 2
1. A.
2. B.
3. C.
4. D.
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Answer: D
Q642023 · 25 Jan 2023 · Shift 2
What is the mass ratio of ethylene glycol $(C_{2} H_{6} O_{2}$ , molar mass = 62 g/mol) required for making 500 g of 0.25 molal aqueous solution and 250 mL of 0.25 molar aqueous solution?
1. A.1 : 2
2. B.1 : 1
3. C.2 : 1
4. D.3 : 1
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Answer: C
Q732023 · 25 Jan 2023 · Shift 2
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R Assertion A : Carbon forms two important oxides - CO and $C O_{2}$ . CO is neutral whereas $C O_{2}$ is acidic in nature Reason R : $C O_{2}$ can combine with water in a limited way to form carbonic acid, while CO is sparingly soluble in water In the light of the above statements, choose the most appropriate answer from the options given below :
1. A.A is not correct but R is correct
2. B.Both A and R are correct but R is NOT the correct explanation of A
3. C.Both A and R are correct and R is the correct explanation of A
4. D.A is correct but R is not correct
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Answer: C
Q842023 · 25 Jan 2023 · Shift 2· Numerical answer
$P t (s) ∣ H_{2} (g) (1 ba r) ∣ H^{+} (a q) (1 M) ∣∣ M^{3 +} (a q), M^{+} (a q) ∣ P t (s)$ The $E_{cell}$ for the given cell is 0.1115 V at 298 K when $\frac{[ M ^{+} ( a q )]}{[ M ^{3 +} ( a q )]} = 1 0^{a}$ The value of $a$ is ____ Given : $E_{M^{3 +} / M^{+}}^{θ} = 0.2$ V $\frac{2.303 R T}{F} = 0.059 V$
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Answer: 3
Q892023 · 25 Jan 2023 · Shift 2· Numerical answer
Based on the given figure, the number of correct statement/s is/are ____. [figure: liquid in a beaker, showing a liquid molecule on the surface and a liquid molecule in the bulk] A. Surface tension is the outcome of equal attractive and repulsive forces acting on the liquid molecule in bulk. B. Surface tension is due to uneven forces acting on the molecules present on the surface. C. The molecule in the bulk can never come to the liquid surface. D. The molecules on the surface are responsible for vapour pressure if the system is a closed system.
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Answer: 2
Q622023 · 24 Jan 2023 · Shift 1
1. A.
2. B.
3. C.
4. D.
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Answer: C