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2021 58 questions

Q822021 · 1 Sept 2021 · Shift 2· Numerical answer
For the reaction, $2 N O_{2} (g) ⇌ N_{2} O_{4} (g)$ , when $Δ S = - 176.0 J K^{- 1}$ and $Δ H = - 57.8 kJ mo l^{- 1}$ , the magnitude of $Δ G$ at $298 K$ for the reaction is ____ $kJ mo l^{- 1}$ . (Nearest integer)
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Answer: 5
Q732021 · 26 Aug 2021 · Shift 2
The interaction energy of London forces between two particles is proportional to $r^{x}$ , where r is the distance between the particles. The value of x is :
1. A. $3$
2. B. $- 3$
3. C. $- 6$
4. D. $6$
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Answer: C
Q802021 · 26 Aug 2021 · Shift 2
Chalcogen group elements are :
1. A.Se, Tb and Pu.
2. B.Se, Te and Po.
3. C.S, Te and Pm.
4. D.O, Ti and Po.
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Answer: B
Q672021 · 27 Jul 2021 · Shift 2
$R - C N (i) D I B A L - H (ii) H_{2} O R - Y$ Consider the above reaction and identify "Y"
1. A. $- C H_{2} N H_{2}$
2. B. $- CON H_{2}$
3. C. $- CHO$
4. D. $- COOH$
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Answer: C
Q682021 · 27 Jul 2021 · Shift 2
1. A.The reaction is not possible in acidic medium
2. B.Both compounds A and B are formed equally
3. C.Compound A will be the major product
4. D.Compound B will be the major product
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Answer: C
Q732021 · 27 Jul 2021 · Shift 2
The number of neutrons and electrons, respectively, present in the radioactive isotope of hydrogen is :
1. A.1 and 1
2. B.3 and 1
3. C.2 and 1
4. D.2 and 2
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Answer: C
Q772021 · 27 Jul 2021 · Shift 2
If the Thomson model of the atom was correct, then the result of Rutherford's gold foil experiment would have been :
1. A.All of the $α$ -particles pass through the gold foil without decrease in speed.
2. B. $α$ -particles are deflected over a wide range of angles.
3. C.All $α$ -particles get bounced back by $18 0^{\circ}$
4. D. $α$ -particles pass through the gold foil deflected by small angles and with reduced speed.
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Answer: D
Q782021 · 27 Jul 2021 · Shift 2
Number of Cl = O bonds in chlorous acid, chloric acid and perchloric acid respectively are :
1. A.3, 1 and 1
2. B.4, 1 and 0
3. C.1, 1 and 3
4. D.1, 2 and 3
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Answer: D
Q822021 · 27 Jul 2021 · Shift 2· Numerical answer
When 400 mL of 0.2 M $H_{2} S O_{4}$ solution is mixed with 600 mL of 0.1 M $NaOH$ solution, the increase in temperature of the final solution is __________ $\times 1 0^{- 2} K$ . (Round off to the nearest integer). [Use : $H^{+} (aq) + O H^{-} (aq) \to H_{2} O : Δ_{r} H = - 57.1 kJ mo l^{- 1}$ ] Specific heat of $H_{2} O = 4.18 J K^{- 1} g^{- 1}$ density of $H_{2} O = 1.0 g c m^{- 3}$ Assume no change in volume of solution on mixing.
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Answer: 82
Q882021 · 27 Jul 2021 · Shift 2· Numerical answer
The dihedral angle in staggered form of Newman projection of 1, 1, 1-Trichloro ethane is ___________ degree. (Round off to the nearest integer)
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Answer: 60
Q702021 · 25 Jul 2021 · Shift 1
Which one of the following compounds of Group-14 elements is not known?
1. A. $[GeC l_{6}]^{2 -}$
2. B. $[Sn (OH)_{6}]^{2 -}$
3. C. $[SiC l_{6}]^{2 -}$
4. D. $[Si F_{6}]^{2 -}$
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Answer: C
Q712021 · 25 Jul 2021 · Shift 1
1. A.
2. B.
3. C.
4. D.
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Answer: A
Q732021 · 25 Jul 2021 · Shift 1
Which one of the following compounds will liberate $C O_{2}$ , when treated with $NaHC O_{3}$ ?
1. A. $(C H_{3})_{3} N \oplus H Cl ⊖$
2. B. $(C H_{3})_{4} N \oplus O ⊖ H$
3. C. $C H_{3} - C ∥ O - N H_{2}$
4. D. $C H_{3} N H_{2}$
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Answer: A
Q752021 · 25 Jul 2021 · Shift 1
1. A.Novolac
2. B.Buna-N
3. C.Acrilan
4. D.Neoprene
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Answer: A
Q792021 · 25 Jul 2021 · Shift 1
Which one of the following chemical agent is not being used for dry-cleaning of clothes?
1. A. $H_{2} O_{2}$
2. B. $CC l_{4}$
3. C.Liquid $C O_{2}$
4. D. $C l_{2} C = CC l_{2}$
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Answer: A
Q892021 · 25 Jul 2021 · Shift 1· Numerical answer
Consider the complete combustion of butane, the amount of butane utilized to produce 72.0 g of water is ____ $\times 1 0^{- 1}$ g. (in nearest integer)
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Answer: 464
Q642021 · 25 Jul 2021 · Shift 2
The correct decreasing order of densities of the following compounds is : (A) [structure: benzene] (B) [structure: chlorobenzene] (C) [structure: 1,3-dichlorobenzene] (D) [structure: 1-bromo-3-chlorobenzene]
1. A.(D) > (C) > (B) > (A)
2. B.(C) > (D) > (A) > (B)
3. C.(C) > (B) > (A) > (D)
4. D.(A) > (B) > (C) > (D)
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Answer: A
Q652021 · 25 Jul 2021 · Shift 2
$C_{6} H_{5} N O_{2} Sn + HCl$ "A" $C_{6} H_{5} N \oplus_{2} Cl ⊖ H^{\oplus}$ P (Yellow coloured Compound) Consider the above reaction, the product "P" is :
1. A.[structure: $C_{6} H_{5} - N = N - C_{6} H_{4} - N H_{2}$ with $N H_{2}$ ortho to the azo group]
2. B.[structure: $C_{6} H_{5} - N = N - C_{6} H_{4} - N H_{2}$ with $N H_{2}$ para to the azo group]
3. C.[structure: $C_{6} H_{5} - NH - C_{6} H_{5}$ ]
4. D.[structure: $C_{6} H_{5} - N = N - NH - C_{6} H_{5}$ ]
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Answer: B
Q682021 · 25 Jul 2021 · Shift 2
1. A.
2. B.
3. C.
4. D.
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Answer: C
Q692021 · 25 Jul 2021 · Shift 2
Identify the species having one $π$ -bond and maximum number of canonical forms from the following :
1. A. $S O_{3}$
2. B. $O_{2}$
3. C. $S O_{2}$
4. D. $C O_{3}^{2 -}$
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Answer: D
Q752021 · 25 Jul 2021 · Shift 2
Which among the following is the strongest acid ?
1. A. $C H_{3} C H_{2} C H_{2} C H_{3}$
2. B.[structure: toluene]
3. C.[structure: cyclopropene]
4. D.[structure: cyclopenta-1,3-diene]
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Answer: D
Q772021 · 25 Jul 2021 · Shift 2
Match List I with List II : $(a) (b) (c) (d) List-I Elements Li Na K Cs (i) (ii) (iii) (iv) List-II Properties Poor water solubility of I^{-} salt Most abundant element in cell fluid Bicarbonate salt used in fire extinguisher Carbonate salt decomposes easily on heating$ Choose the correct answer from the options given below :
1. A.(a)-(iv), (b)-(iii), (c)-(ii), (d)-(i)
2. B.(a)-(i), (b)-(iii), (c)-(ii), (d)-(iv)
3. C.(a)-(iv), (b)-(ii), (c)-(iii), (d)-(i)
4. D.(a)-(i), (b)-(ii), (c)-(iii), (d)-(iv)
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Answer: A
Q862021 · 25 Jul 2021 · Shift 2· Numerical answer
Assuming that $Ba (OH)_{2}$ is completely ionised in aqueous solution under the given conditions the concentration of $H_{3} O^{+}$ ions in 0.005 M aqueous solution of $Ba (OH)_{2}$ at 298 K is ____ $\times 1 0^{- 12} mol L^{- 1}$ . (Nearest integer)
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Answer: 1
Q892021 · 25 Jul 2021 · Shift 2· Numerical answer
The number of significant figures in 0.00340 is ____________.
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Answer: 3
Q612021 · 22 Jul 2021 · Shift 2
Which one of the following statements for D.I. Mendeleeff, is incorrect?
1. A.He authored the textbook - Principles of Chemistry
2. B.At the time, he proposed Periodic Table of elements structure of atom was known.
3. C.Element with atomic number 101 is named after him.
4. D.He invented accurate barometer.
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Answer: B