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2020 54 questions

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.
Show answer
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
Q752020 · 2 Sept 2020 · Shift 1· Numerical answer
The mass of gas adsorbed, x, per unit mass of adsorbate, m, was measured at various pressures, p. A graph between $lo g \frac{x}{m}$ and $lo g p$ gives a straight line with slope equal to 2 and the intercept equal to 0.4771. The value of $\frac{x}{m}$ at a pressure of 4 atm is : (Given $lo g 3 = 0.4771$ )
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Answer: 48
Q542020 · 2 Sept 2020 · Shift 2
1. A. $b > c > d > a$
2. B. $b > a > c > d$
3. C. $c > b > d > a$
4. D. $c > b > a > d$
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Answer: A
Q562020 · 2 Sept 2020 · Shift 2
If you spill a chemical toilet cleaning liquid on your hand, your first aid would be
1. A.aqueous $NaOH$
2. B.aqueous $NaHC O_{3}$
3. C.aqueous $N H_{3}$
4. D.vinegar
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Answer: B
Q582020 · 2 Sept 2020 · Shift 2
The size of a raw mango shrinks to a much smaller size when kept in a concentrated salt solution. Which one of the following processes can explain this?
1. A.Osmosis
2. B.Reverse osmosis
3. C.Diffusion
4. D.Dialysis
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Answer: A
Q592020 · 2 Sept 2020 · Shift 2
Match the type of interaction in column A with the distance dependence of their interaction energy in column B | A | B | | :--- | :--- | | (i) ion-ion | (a) $\frac{1}{r}$ | | (ii) dipole-dipole | (b) $\frac{1}{r ^{2}}$ | | (iii) London dispersion | (c) $\frac{1}{r ^{3}}$ | | | (d) $\frac{1}{r ^{6}}$ |
1. A.(I)-(a), (II)-(b), (III)-(d)
2. B.(I)-(b), (II)-(d), (III)-(c)
3. C.(I)-(a), (II)-(b), (III)-(c)
4. D.(I)-(a), (II)-(c), (III)-(d)
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Answer: D
Q582020 · 9 Jan 2020 · Shift 1
1. A.(iii) < (i) < (ii) < (iv) < (v)
2. B.(iii) < (iv) < (ii) < (i) < (v)
3. C.(v) < (i) < (iv) < (ii) < (iii)
4. D.(v) < (iii) < (ii) < (iv) < (i)
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Answer: D
Q602020 · 9 Jan 2020 · Shift 1
The acidic, basic and amphoteric oxides, respectively, are :
1. A. $C l_{2} O$ , $CaO$ , $P_{4} O_{10}$
2. B. $N_{2} O_{3}$ , $L i_{2} O$ , $A l_{2} O_{3}$
3. C. $MgO$ , $C l_{2} O$ , $A l_{2} O_{3}$
4. D. $N a_{2} O$ , $S O_{3}$ , $A l_{2} O_{3}$
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Answer: B
Q692020 · 9 Jan 2020 · Shift 1
'X' melts at low temperature and is a bad conductor of electricity in both liquid and solid state. X is :
1. A.Mercury
2. B.Carbon tetrachloride
3. C.Zinc sulphide
4. D.Silicon carbide
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Answer: B
Q552020 · 9 Jan 2020 · Shift 2
Which of the following has the shortest C-Cl bond?
1. A. $Cl - CH = CH - C H_{3}$
2. B. $Cl - CH = CH - N O_{2}$
3. C. $Cl - CH = CH - OC H_{3}$
4. D. $Cl - CH = C H_{2}$
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Answer: B