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2023 96 questions

Q632023 · 10 Apr 2023 · Shift 2
1. A.
2. B.
3. C.
4. D.
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Answer: A
Q652023 · 10 Apr 2023 · Shift 2
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A : $3.1500 g$ of hydrated oxalic acid dissolved in water to make $250.0 mL$ solution will result in 0.1 M oxalic acid solution. Reason R : Molar mass of hydrated oxalic acid is $126 g mol^{- 1}$ In the light of the above statements, choose the correct answer from the options given below.
1. A.Both A and R are true but R is NOT the correct explanation of A
2. B.A is true but R is false
3. C.Both A and R are true and R is the correct explanation of A
4. D.A is false but R is true
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Answer: C
Q672023 · 10 Apr 2023 · Shift 2
1. A.E > C > D > A > B
2. B.D > E > C > A > B
3. C.E > D > C > B > A
4. D.C > E > D > B > A
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Answer: A
Q732023 · 10 Apr 2023 · Shift 2
Given below are two statements: one is labelled as Assertion A and the other is labelled as Reason R Assertion A : Physical properties of isotopes of hydrogen are different. Reason R : Mass difference between isotopes of hydrogen is very large. In the light of the above statements, choose the correct answer from the options given below:
1. A.A is true but R is false
2. B.Both A and R are true but R is NOT the correct explanation of A
3. C.A is false but R is true
4. D.Both A and R are true and R is the correct explanation of A
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Answer: D
Q762023 · 10 Apr 2023 · Shift 2
Ferric chloride is applied to stop bleeding because -
1. A. $FeCl_{3}$ reacts with the constituents of blood which is a positively charged sol.
2. B.Blood absorbs $FeCl_{3}$ and forms a complex.
3. C. $Cl^{-}$ ions cause coagulation of blood.
4. D. $Fe^{3 +}$ ions coagulate blood which is a negatively charged sol.
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Answer: D
Q802023 · 10 Apr 2023 · Shift 2
The delicate balance of $CO_{2}$ and $O_{2}$ is NOT disturbed by :
1. A.Burning of Coal
2. B.Burning of petroleum
3. C.Respiration
4. D.Deforestation
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Answer: C
Q862023 · 10 Apr 2023 · Shift 2· Numerical answer
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Answer: 1
Q882023 · 10 Apr 2023 · Shift 2· Numerical answer
$A(g) ⇌ 2 B(g) + C(g)$ For the given reaction, if the initial pressure is 450 mm Hg and the pressure at time $t$ is 720 mm Hg at a constant temperature T and constant volume V. The fraction of A(g) decomposed under these conditions is $x \times 1 0^{- 1}$ . The value of $x$ is _________ (nearest integer)
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Answer: 3
Q652023 · 8 Apr 2023 · Shift 1
$2 IO_{3}^{-} + x I^{-} + 12 H^{+} \to 6 I_{2} + 6 H_{2} O$ What is the value of $x$ ?
1. A. $10$
2. B. $2$
3. C. $12$
4. D. $6$
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Answer: A
Q882023 · 8 Apr 2023 · Shift 1· Numerical answer
The number of following statement/s which is/are incorrect is ___________ (A) Line emission spectra are used to study the electronic structure (B) The emission spectra of atoms in the gas phase show a continuous spread of wavelength from red to violet (C) An absorption spectrum is like the photographic negative of an emission spectrum (D) The element helium was discovered in the sun by spectroscopic method
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Answer: 1
Q902023 · 8 Apr 2023 · Shift 1· Numerical answer
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Answer: 3
Q622023 · 8 Apr 2023 · Shift 2
1. A.2 - Formyl -5-methylhexan-6-oic acid
2. B.5-Methyl-2-oxohexan-6-oic acid
3. C.5-Formyl -2-methylhexanoic acid
4. D.2-Methyl-5-oxohexanoic acid
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Answer: D
Q702023 · 8 Apr 2023 · Shift 2
1. A.
2. B.
3. C.
4. D.
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Answer: A
Q742023 · 8 Apr 2023 · Shift 2
Which of the following have same number of significant figures? A. 0.00253 B. 1.0003 C. 15.0 D. 163 Choose the correct answer from the options given below
1. A.A, C and D only
2. B.B and C only
3. C.A, B and C only
4. D.C and D only
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Answer: A
Q782023 · 8 Apr 2023 · Shift 2
In Hall - Heroult process, the following is used for reducing $A l_{2} O_{3}$ :-
1. A.Magnesium
2. B. $Ca F_{2}$
3. C.Graphite
4. D. $N a_{3} Al F_{6}$
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Answer: C
Q802023 · 8 Apr 2023 · Shift 2
Which of the following can reduce decomposition of $H_{2} O_{2}$ on exposure to light :
1. A.Urea
2. B.Glass containers
3. C.Alkali
4. D.Dust
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Answer: A
Q902023 · 8 Apr 2023 · Shift 2· Numerical answer
Coagulating value of the electrolytes $AlC l_{3}$ and $NaCl$ for $A s_{2} S_{3}$ are $0.09$ and $50.04$ respectively. The coagulating power of $AlC l_{3}$ is $x$ times the coagulating power of $NaCl$ . The value of $\underline{x}$ is ____.
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Answer: 556
Q672023 · 6 Apr 2023 · Shift 1
Match List I with List II | LIST I (Oxide) | LIST II (Type of bond) | | :--- | :--- | | A. $N_{2} O_{4}$ | I. $1 N = O bond$ | | B. $NO_{2}$ | II. $1 N - O - N bond$ | | C. $N_{2} O_{5}$ | III. $1 N - N bond$ | | D. $N_{2} O$ | IV. $1 N = N / N \equiv N bond$ | Choose the correct answer from the options given below:
1. A.A-II, B-I, C-III, D-IV
2. B.A-III, B-I, C-II, D-IV
3. C.A-III, B-I, C-IV, D-II
4. D.A-II, B-IV, C-III, D-I
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Answer: B
Q682023 · 6 Apr 2023 · Shift 1
The difference between electron gain enthalpies will be maximum between :
1. A.Ar and Cl
2. B.Ne and Cl
3. C.Ne and F
4. D.Ar and F
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Answer: B
Q772023 · 6 Apr 2023 · Shift 1
Given below are two statements, one is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Loss of electron from hydrogen atom results in nucleus of $\sim 1.5 \times 1 0^{- 3} pm$ size. Reason R : Proton ( $H^{+}$ ) always exists in combined form. In the light of the above statements, choose the most appropriate answer from the options given below:
1. A.Both A and R are correct and R is the correct explanation of A
2. B.A is correct but R is not correct
3. C.A is not correct but R is correct
4. D.Both A and R are correct but R is NOT the correct explanation of A
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Answer: D
Q812023 · 6 Apr 2023 · Shift 1· Numerical answer
Number of bromo derivatives obtained on treating ethane with excess of $Br_{2}$ in diffused sunlight is ________
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Answer: 9
Q822023 · 6 Apr 2023 · Shift 1· Numerical answer
The wavelength of an electron of kinetic energy $4.50 \times 1 0^{- 29} J$ is ________ $\times 1 0^{- 5} m$ . (Nearest integer) Given : mass of electron is $9 \times 1 0^{- 31} kg$ , $h = 6.6 \times 1 0^{- 34} J s$
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Answer: 7
Q832023 · 6 Apr 2023 · Shift 1· Numerical answer
The number of species from the following which have square pyramidal structure is ________ $PF_{5}, BrF_{4}^{-}, IF_{5}, BrF_{5}, XeOF_{4}, ICl_{4}^{-}$
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Answer: 3
Q862023 · 6 Apr 2023 · Shift 1· Numerical answer
The value of $lo g K$ for the reaction $A ⇌ B$ at $298 K$ is ________. (Nearest integer) Given: $Δ H^{\circ} = - 54.07 kJ mol^{- 1}$ $Δ S^{\circ} = 10 J K^{- 1} mol^{- 1}$ (Take $2.303 \times 8.314 \times 298 = 5705$ )
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Answer: 10
Q662023 · 6 Apr 2023 · Shift 2
Which one of the following elements will remain as liquid inside pure boiling water?
1. A.Li
2. B.Br
3. C.Cs
4. D.Ga
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Answer: D