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2020 54 questions

Q512020 · 6 Sept 2020 · Shift 1
1. A. $I < II < IV < III$
2. B. $I < II < III < IV$
3. C. $II < I < III < IV$
4. D. $II < IV < III < I$
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Answer: A
Q662020 · 6 Sept 2020 · Shift 1
The incorrect statement is :
1. A.bronze is an alloy of copper and tin
2. B.cast iron is used to manufacture wrought iron
3. C.german silver is an alloy of zinc, copper and nickel
4. D.brass is an alloy of copper and nickel
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Answer: D
Q672020 · 6 Sept 2020 · Shift 1
Kraft temperature is the temperature :
1. A.below which the aqueous solution of detergents starts freezing.
2. B.above which the formation of micelles takes place.
3. C.below which the formation of micelles takes place.
4. D.above which the aqueous solution of detergents starts boiling.
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Answer: B
Q742020 · 6 Sept 2020 · Shift 1· Numerical answer
The number of Cl = O bonds in perchloric acid is, "________".
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Answer: 3
Q752020 · 6 Sept 2020 · Shift 1· Numerical answer
A spherical balloon of radius $3 cm$ containing helium gas has a pressure of $48 \times 1 0^{- 3} bar$ . At the same temperature, the pressure, of a spherical balloon of radius $12 cm$ containing the same amount of gas will be ______ $\times 1 0^{- 6} bar$ .
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Answer: 750
Q512020 · 6 Sept 2020 · Shift 2
Which one of the following statements is not true?
1. A.Lactose contains $α$ -glycosidic linkage between $C_{1}$ of galactose and $C_{4}$ of glucose
2. B.Lactose is a reducing sugar and it gives Fehling’s test
3. C.On acid hydrolysis, lactose gives one molecule of D(+)-glucose and one molecule of D(+)-galactose
4. D.Lactose ( $C_{12} H_{22} O_{11}$ ) is a disaccharide and it contains 8 hydroxyl groups
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Answer: A
Q542020 · 6 Sept 2020 · Shift 2
Mischmetal is an alloy consisting mainly of :
1. A.lanthanoid and actinoid metals
2. B.actinoid and transition metals
3. C.lanthanoid metals
4. D.actinoid metals
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Answer: C
Q582020 · 6 Sept 2020 · Shift 2
A set of solutions is prepared using 180 g of water as a solvent and 10 g of different nonvolatile solutes A, B and C. The relative lowering of vapour pressure in the presence of these solutes are in the order : $[Given, molar mass of A = 100 g mo l^{- 1}; B = 200 g mo l^{- 1}; C = 10, 000 g mo l^{- 1}]$
1. A. $A > C > B$
2. B. $C > B > A$
3. C. $A > B > C$
4. D. $B > C > A$
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Answer: C
Q632020 · 6 Sept 2020 · Shift 2
The reaction of NO with $N_{2} O_{4}$ at 250 K gives :
1. A. $N_{2} O_{3}$
2. B. $N_{2} O_{5}$
3. C. $N_{2} O$
4. D. $N O_{2}$
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Answer: A
Q662020 · 6 Sept 2020 · Shift 2
Reaction of an inorganic sulphite X with dilute $H_{2} S O_{4}$ generates compound Y. Reaction of Y with $NaOH$ gives X. Further, the reaction of X with Y and water affords compound Z. Y and Z, respectively, are :
1. A. $S$ and $N a_{2} S O_{3}$
2. B. $S O_{2}$ and $NaHS O_{3}$
3. C. $S O_{2}$ and $N a_{2} S O_{3}$
4. D. $S O_{3}$ and $NaHS O_{3}$
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Answer: B
Q682020 · 6 Sept 2020 · Shift 2
For a reaction, $4M (s) + n O_{2} (g) \to 2 M_{2} O_{n} (s)$ the free energy change is plotted as a function of temperature. The temperature below which the oxide is stable could be inferred from the plot as the point at which :
1. A.the free energy change shows a change from negative to positive value
2. B.the slope changes from positive to negative
3. C.the slope changes from negative to positive
4. D.the slope changes from positive to zero
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Answer: A
Q702020 · 6 Sept 2020 · Shift 2
Dihydrogen of high purity (> 99.95%) is obtained through :
1. A.the electrolysis of acidified water using Pt electrodes
2. B.the electrolysis of warm $Ba (OH)_{2}$ solution using Ni electrodes
3. C.the electrolysis of brine solution
4. D.the reaction of Zn with dilute HCl
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Answer: B
Q512020 · 3 Sept 2020 · Shift 1
It is true that :
1. A.A first order reaction is always a single step reaction
2. B.A zero order reaction is a multistep reaction
3. C.A zero order reaction is a single step reaction
4. D.A second order reaction is always a multistep reaction
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Answer: B
Q552020 · 3 Sept 2020 · Shift 1
1. A.
2. B.
3. C.
4. D.
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Answer: D
Q572020 · 3 Sept 2020 · Shift 1
Of the species, $NO, N O^{+}, N O^{2 +}$ and $N O^{-}$ , the one with minimum bond strength is :
1. A. $N O^{-}$
2. B. $NO$
3. C. $N O^{+}$
4. D. $N O^{2 +}$
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Answer: A
Q592020 · 3 Sept 2020 · Shift 1
Henry's constant (in kbar) for four gases $α, β, γ$ and $δ$ in water at 298 K is given below : | | $α$ | $β$ | $γ$ | $δ$ | | :--- | :--- | :--- | :--- | :--- | | $K_{H}$ | 50 | 2 | $2 \times 1 0^{- 5}$ | 0.5 | (density of water $= 1 0^{3} kg m^{- 3}$ at 298 K) This table implies that :
1. A.solubility of $γ$ at 308 K is lower than at 298 K
2. B.The pressure of a 55.5 molal solution of $δ$ is 250 bar
3. C. $α$ has the highest solubility in water at a given pressure
4. D.The pressure of a 55.5 molal solution of $γ$ is 1 bar
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Answer: A, B
Q662020 · 3 Sept 2020 · Shift 1
Aqua regia is used for dissolving noble metals (Au, Pt, etc.). The gas evolved in this process is :
1. A. $N_{2} O_{3}$
2. B. $N_{2}$
3. C. $N_{2} O_{5}$
4. D. $NO$
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Answer: D
Q682020 · 3 Sept 2020 · Shift 1
Thermal power plants can lead to :
1. A.Ozone layer depletion
2. B.Blue baby syndrome
3. C.Eutrophication
4. D.Acid rain
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Answer: D
Q722020 · 3 Sept 2020 · Shift 1· Numerical answer
The volume strength of 8.9 M $H_{2} O_{2}$ solution calculated at 273 K and 1 atm is _______. ( $R = 0.0821 L atm K^{- 1} mo l^{- 1}$ ) (rounded off ot the nearest integer)
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Answer: 100
Q612020 · 3 Sept 2020 · Shift 2
The incorrect statement is :
1. A.In manganate and permanganate ions, the π-bonding takes place by overlap of p-orbitals of oxygen and d-orbitals of manganese
2. B.Manganate ion is green in colour and permanganate ion is purple in colour
3. C.Manganate and permanganate ions are paramagnetic
4. D.Manganate and permanganate ions are tetrahedral
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Answer: C
Q652020 · 3 Sept 2020 · Shift 2
For the reaction $2 A + 3 B + \frac{3}{2} C \to 3 P$ , which statement is correct ?
1. A. $\frac{d n _{A}}{d t} = \frac{d n _{B}}{d t} = \frac{d n _{C}}{d t}$
2. B. $\frac{d n _{A}}{d t} = \frac{2}{3} \frac{d n _{B}}{d t} = \frac{3}{4} \frac{d n _{C}}{d t}$
3. C. $\frac{d n _{A}}{d t} = \frac{3}{2} \frac{d n _{B}}{d t} = \frac{3}{4} \frac{d n _{C}}{d t}$
4. D. $\frac{d n _{A}}{d t} = \frac{2}{3} \frac{d n _{B}}{d t} = \frac{4}{3} \frac{d n _{C}}{d t}$
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Answer: D
Q522020 · 2 Sept 2020 · Shift 1
1. A.
2. B.
3. C.
4. D.
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Answer: A
Q622020 · 2 Sept 2020 · Shift 1
While titrating dilute HCl solution with aqueous NaOH, which of the following will not be required?
1. A.Pipette and distilled water
2. B.Clamp and phenolphthalein
3. C.Burette and porcelain tile
4. D.Bunsen burner and measuring cylinder
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Answer: D
Q642020 · 2 Sept 2020 · Shift 1
In general the property (magnitudes only) that show an opposite trend in comparison to other properties across a period is
1. A.Electron gain enthalpy
2. B.Electronegativity
3. C.Ionization enthalpy
4. D.Atomic radius
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Answer: D
Q652020 · 2 Sept 2020 · Shift 1
1. A.(iii) < (iv) < (ii) < (i)
2. B.(i) < (iii) < (iv) < (ii)
3. C.(iii) < (i) < (iv) < (ii)
4. D.(iii) < (iv) < (i) < (ii)
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Answer: C