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2021 58 questions

Q632021 · 20 Jul 2021 · Shift 1
The correct order of intensity of colors of the compounds is :
1. A. $[Ni (CN)_{4}]^{2 -} > [NiCl_{4}]^{2 -} > [Ni (H_{2} O)_{6}]^{2 +}$
2. B. $[Ni (H_{2} O)_{6}]^{2 +} > [NiCl_{4}]^{2 -} > [Ni (CN)_{4}]^{2 -}$
3. C. $[NiCl_{4}]^{2 -} > [Ni (H_{2} O)_{6}]^{2 +} > [Ni (CN)_{4}]^{2 -}$
4. D. $[NiCl_{4}]^{2 -} > [Ni (CN)_{4}]^{2 -} > [Ni (H_{2} O)_{6}]^{2 +}$
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Answer: C
Q682021 · 20 Jul 2021 · Shift 1
Compound A is converted to B on reaction with $CHCl_{3}$ and $KOH$ . The compound B is toxic and can be decomposed by C. A, B and C respectively are :
1. A.primary amine, nitrile compound, conc. $HCl$
2. B.secondary amine, isonitrile compound, conc. $NaOH$
3. C.primary amine, isonitrile compound, conc. $HCl$
4. D.secondary amine, nitrile compound, conc. $NaOH$
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Answer: C
Q692021 · 20 Jul 2021 · Shift 1
Identify the incorrect statement from the following
1. A.Amylose is a branched chain polymer of glucose
2. B.Starch is a polymer of $α$ -D glucose
3. C. $β$ -Glycosidic linkage makes cellulose polymer
4. D.Glycogen is called as animal starch
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Answer: A
Q732021 · 20 Jul 2021 · Shift 1
The set in which compounds have different nature is :
1. A. $B(OH)_{3}$ and $H_{3} PO_{3}$
2. B. $B(OH)_{3}$ and $Al(OH)_{3}$
3. C. $NaOH$ and $Ca(OH)_{2}$
4. D. $Be(OH)_{2}$ and $Al(OH)_{3}$
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Answer: B
Q742021 · 20 Jul 2021 · Shift 1
Given below are two statements. One is labelled as Assertion A and the other is labelled as Reason R. Assertion A : Sharp glass edge becomes smooth on heating it upto its melting point. Reason R : The viscosity of glass decreases on melting. Choose the most appropriate 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: B
Q752021 · 20 Jul 2021 · Shift 1
Orlon fibres are made up of :
1. A.Polyacrylonitrile
2. B.Polyesters
3. C.Polyamide
4. D.Cellulose
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Answer: A
Q762021 · 20 Jul 2021 · Shift 1
Given below are two statements : One is labelled as Assertion A and other is labelled as Reason R. Assertion A : The dihedral angles in $H_{2} O_{2}$ in gaseous phase is $90. 2^{\circ}$ and in solid phase is $111. 5^{\circ}$ . Reason R : The change in dihedral angle in solid and gaseous phase is due to the difference in the intermolecular forces. Choose the most appropriate answer from the options given below for A and R.
1. A.A is correct but R is not 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 not correct but R is correct.
Show answer
Answer: D
Q822021 · 20 Jul 2021 · Shift 1· Numerical answer
$250 mL$ of $0.5 M$ $NaOH$ was added to $500 mL$ of $1 M$ $HCl$ . The number of unreacted $HCl$ molecules in the solution after complete reaction is ________ $\times 1 0^{21}$ . (Nearest integer) ( $N_{A} = 6.022 \times 1 0^{23}$ )
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Answer: 226
Q652021 · 18 Mar 2021 · Shift 1
A non-reducing sugar "A" hydrolyses to give two reducing mono saccharides. Sugar A is
1. A.Fructose
2. B.Galactose
3. C.Glucose
4. D.Sucrose
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Answer: D
Q852021 · 18 Mar 2021 · Shift 1· Numerical answer
____ grams of 3-Hydroxy propanal (MW = 74) must be dehydrated to produce 7.8 g of acrolein (MW = 56) ( $C_{3} H_{4} O$ ) if the percentage yield is 64. (Round off to the Nearest Integer). [Given : Atomic masses : C : 12.0 u, H : 1.0 u, O : 16.0 u ]
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Answer: 16
Q902021 · 18 Mar 2021 · Shift 1· Numerical answer
Complete combustion of 3g of ethane gives $x \times 1 0^{22}$ molecules of water. The value of x is ____. (Round off to the Nearest Integer). [Use : $N_{A} = 6.023 \times 1 0^{23}$ ; Atomic masses in u : C : 12.0; O : 16.0; H : 1.0]
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Answer: 18
Q652021 · 18 Mar 2021 · Shift 2
The oxide that shows magnetic property is :
1. A. $MgO$
2. B. $Si O_{2}$
3. C. $M n_{3} O_{4}$
4. D. $N a_{2} O$
Show answer
Answer: C
Q722021 · 18 Mar 2021 · Shift 2
1. A.
2. B.
3. C.
4. D.
Show answer
Answer: D
Q732021 · 18 Mar 2021 · Shift 2
1. A.
2. B.
3. C.
4. D.
Show answer
Answer: A
Q762021 · 18 Mar 2021 · Shift 2
A hard substance melts at high temperature and is an insulator in both solid and in molten state. This solid is most likely to be a/an :
1. A.Covalent solid
2. B.Molecular solid
3. C.Ionic solid
4. D.Metallic solid
Show answer
Answer: A
Q822021 · 18 Mar 2021 · Shift 2· Numerical answer
$10.0 mL$ of $N a_{2} C O_{3}$ solution is titrated against $0.2 M$ $HCl$ solution. The following titre values were obtained in 5 readings : $4.8 mL, 4.9 mL, 5.0 mL, 5.0 mL$ and $5.0 mL$ Based on these readings, and convention of titrimetric estimation the concentration of $N a_{2} C O_{3}$ solution is ____ $mM$ . (Round off to the Nearest Integer).
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Answer: 50
Q882021 · 18 Mar 2021 · Shift 2· Numerical answer
The solubility of $CdS O_{4}$ in water is $8.0 \times 1 0^{- 4} mol L^{- 1}$ . Its solubility in $0.01 M$ $H_{2} S O_{4}$ solution is ____ $\times 1 0^{- 6} mol L^{- 1}$ . (Round off to the Nearest Integer). (Assume that solubility is much less than $0.01 M$ )
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Answer: 64
Q792021 · 16 Mar 2021 · Shift 1
Given below are two statements : Statement I : Both $CaC l_{2} \cdot 6 H_{2} O$ and $MgC l_{2} \cdot 8 H_{2} O$ undergo dehydration on heating. Statement II : $BeO$ is amphoteric whereas the oxides of other elements in the same group are acidic. In the light of the above statements, choose the correct answer from the options given below :
1. A.Both statement I and statement II are false
2. B.Statement I is false but statement II is true
3. C.Statement I is true but statement II is false
4. D.Both statement I and statement II are true
Show answer
Answer: A
Q852021 · 16 Mar 2021 · Shift 1· Numerical answer
$2 Mn O_{4}^{-} + b C_{2} O_{4}^{2 -} + c H^{+} \to x M n^{2 +} + y C O_{2} + z H_{2} O$ If the above equation is balanced with integer coefficients, the value of c is _______. (Round off to the Nearest Integer).
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Answer: 16
Q622021 · 26 Feb 2021 · Shift 1
Which of the following is 'a' FALSE statement ?
1. A.Carius method is used for the estimation of nitrogen in an organic compound.
2. B.Kjeldahl's method is used for the estimation of nitrogen in an organic compound.
3. C.Carius tube is used in the estimation of sulphur in an organic compound.
4. D.Phosphoric acid produced on oxidation of phosphorus present in an organic compound is precipitated as $M g_{2} P_{2} O_{7}$ by adding magnesia mixture.
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Answer: A
Q792021 · 26 Feb 2021 · Shift 1
On treating a compound with warm dil. $H_{2} S O_{4}$ , gas X is evolved which turns $K_{2} C r_{2} O_{7}$ paper acidified with dil. $H_{2} S O_{4}$ to a green compound Y. X and Y respectively are :
1. A. $X = S O_{2}, Y = C r_{2} O_{3}$
2. B. $X = S O_{3}, Y = C r_{2} (S O_{4})_{3}$
3. C. $X = S O_{3}, Y = C r_{2} O_{3}$
4. D. $X = S O_{2}, Y = C r_{2} (S O_{4})_{3}$
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Answer: D
Q892021 · 26 Feb 2021 · Shift 1· Numerical answer
The number of significant figures in $50000.020 \times 1 0^{- 3}$ is _________.
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Answer: 8
Q662021 · 26 Feb 2021 · Shift 2
Which of the following forms of hydrogen emits low energy $β^{-}$ particles?
1. A.Tritium $_{1}^{3} H$
2. B.Proton $H^{+}$
3. C.Protium $_{1}^{1} H$
4. D.Deuterium $_{1}^{2} H$
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Answer: A
Q672021 · 26 Feb 2021 · Shift 2
Which pair of oxides is acidic in nature?
1. A. $CaO, Si O_{2}$
2. B. $B_{2} O_{3}, CaO$
3. C. $B_{2} O_{3}, Si O_{2}$
4. D. $N_{2} O, BaO$
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Answer: C
Q712021 · 26 Feb 2021 · Shift 2
2, 4-DNP test can be used to identify :
1. A.ether
2. B.amine
3. C.aldehyde
4. D.halogens
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Answer: C