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The trans- alkenes are formed by the reduction of alkynes with

A) $H_{2}-Pd/C,BaSO_{4}$

B) $NaBH_{4}$

C) $Na/liq.NH_{3}$

D) $Sn-HCL$

An aqueous solution contains 0.10 M H₂S and 0.20 M HCl. If the equilibrium constants for the formation of HS^- from H₂S is 1.0×10^-7 and that of S^2- from HS^- ions is 1.2×10^-13 then the concentration of S^2-ions in aqueous solution is

A) $5\times 10^{-8}$

B) $3\times 10^{-20}$

C) $6\times 10^{-21}$

D) $5\times 10^{-19}$

The oxidation states of Cr, in [Cr(H₂O)₆Cl₃ , [Cr(C₆H₆)₂] and K₂[Cr (CN)₂(O)₂ (O₂ )(NH₃)] respectively are

A) +3, +4 and +6

B) +3, +2 and +4

C) +3, 0 and +6

D) +3, 0 and +4

When metal 'M' is treated with NaOH , a while gelatinous precipitate 'X' is obtained, which is soluble in excess of NaOH. Compound 'X' when heated strongly gives an oxide which is used in chromatography as an adsorbent. The metal 'M' is

A) Zn

B) Ca

C) Al

D) Fe

The correct statement(s) regarding the binary transition metal carbonyl compounds is (are) [Atomic numbers : Fe=26, Ni= 28]

A) Total number of valence shell electrons at metal centre in $Fe (CO)_{5}$ or $Ni (CO)_{4}$ is 16

B) These are predominantly low spin in nature

C) Metal- carbon bond strengthens when the oxidation state of the metal is lowered

D) The carbonyl C-O bond weakens when the oxidation state of the metal is increased

A reversible cyclic process for an ideal gas is shown below. Hence , P , V and T are pressure, volume and temperature respectively , The thermodynamic parameters q,w, H and U are heat, work, enthalpy and internal energy, respectively.

The correct options is (are)

A) $q_{AC}=\triangle U_{BC}$ and $w_{AB}=p_{2}(V_{2}-V_{1})$

B) $w_{BC}=p_{2}(V_{2}-V_{1})$ and $q_{BC}=\triangle H_{AC}$

C) $\triangle H_{CA}<\triangle U_{CA}$ and $q_{AC}=\triangle U_{BC}$

D) $q_{BC}=\triangle H_{AC}$ and $\triangle H_{CA}>\triangle U_{CA}$

The ammonia prepared by treating ammonium sulphate with calcium hydroxide is completely used by NiCl₂. 6H₂O to form a stable coordination compound. Assume that both the reactions are 100% complete. If 1584 g of ammonium sulphate and 952 g of NiCl₂ .6H₂O are used in the preparation, the combined weight (in grams)of gypsum and the nickel -ammonia coordination compound thus produced is ......

(Atomic weights is g mol-1:H=1,N=14, O=16, S=32, Cl=35.5, Ca=40, Ni=59)

A) 2992

B) 2064

C) 2890

D) 2994

For the electrochemical cell,

Mg(s) | Mg ²⁺ (aq. 1M)|

|Cu²⁺ (aq. 1M)| Cu(s)

The standard emf of the cell is 2.70V at 300K. When the concentration of Mg ²⁺ is changed to x M, the cell potential changes to 2.67 V at 300K. The value of x is .............. [ Given, $\frac{F}{R}=11500KV^{-1}$, where F is the Faraday constant and R is the gas contant, ln (10)=2.30)

A) 10

B) 8

C) 5

D) 15

A closed tank has two compartments A and B , both filled with oxygen (assumed to be ideal gas) . The partition separating the two compartments is fixed and is a perfect heat insulator (Fig .1) . If the old partition is replaced by a new partition which can slide and conduct heat but does not allow the gas to leak across (Fig. 2) , the volume ( in m³ ) of the compartment A after the system attains equilibrium is................

A) 2.82

B) 2.22

C) 3

D) 1.8

The solubility of salt of a weak acid (AB) at pH 3 is Y× 10^-3 mol L^-1. The value of Y is.........

[Given that the value of solubility product of AB (K_sp)=2× 10^-10 and the value of ionization constant of HB (K_a)=1× 10^-8]

A) 5

B) 4.47

C) 8.2

D) 3.8

The plot given below shows p-T curves (where p is the pressure and T is the temperature ) for two solvents X and Y and isolmolal solution of NaCl these solvents. NaCl completely dissociates in both the solvents

On the addition of the equal number of moles of a non -volatile S in equal amount (in kg) of these solvents, the elevation of boiling point X is three times that of solvent Y. Solute S is known to undergo dimerization in these solvents. If the degree of dimerization is 0.7 in solvent Y, the degree of dimerization in solvent X is...........

A) 0.05

B) 0.09

C) 0.01

D) 1

The correct option (s) regarding the complex [Co(en)(NH₃)₃ (H₂O)]³⁺ (en=H₂NCH₂CH₂NH₂) is (are)

A) It has two geometrical isomers

B) It will have three geometrical isomers, if bidentate 'en' is replaced by two cyanide ligands

C) It is paramagnetic

D) It absorbs light at longer wavelength as compared to $[Co(en)(NH_{3})_{4}]^{3+}$

The correct options (s) to distinguish nitrate salts to Mn²⁺ and Cu²⁺ taken separately is (are)

A) $Mn^{2+}$ shows the characteristic green colour in the flame test

B) Only $Cu^{2+}$ shows the formation of precipitate by passing $H_{2}S$ in acidic medium.

C) Only $Mn^{2+}$ shows the formation of precipitate by passing $H_{2}S$ in faintly basic medium.

D) $Cu^{2+}$/Cu has higher reduction potential than $Mn^{2+}$/Mn ( measured under similar conditions)

For a reaction , $A\rightleftharpoons P,$ the plots of [A] and [P] with time at temperature T₁ and T₂ are given below.

If T₂> T₁ , the correct statement (s) is /are

[ Assume $\triangle H^{\ominus}$ and $\triangle S^{\ominus}$ are independent of temperature and ratio of ln K at T₁ to ln K at T₂ is greater than T2/T1. Here H, S, G and K are enthalpy, entropy, Gibbs energy and equilibrium constant, respectively.)

A) $\triangle H^{\ominus}<0, \triangle S^{\ominus}<0$

B) $\triangle G^{\ominus}<0, \triangle H^{\ominus}>0$

C) $\triangle G^{\ominus}<0, \triangle S^{\ominus}<0$

D) $\triangle G^{\ominus}<0, \triangle S^{\ominus}>0$

The total number of compounds having at least one bridging oxo group amoung the molecule given below...

N₂O₃ ,N₂O₅ ,P₄ O₆ , P₄O₇, H₄P₂O_5,H₅P₃O₁₀, H₂S₂O₃, H₂S₂O₅

A) 6

B) 8

C) 4

D) 2

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