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According to molecular orbital theory, which of the following will not be a viable molecule?

A) $He_{2}^{2+}$

B) $He_{2}^{+}$

C) $H_{2}^{2-}$

D) $H_{2}^{-}$

Which of the following are Lewis acids?

A) $PH_{3}$ and $BCl_{3}$

B) $AlCl_{3}$ and $SiCl_{4}$

C) $BCl_{3}$ and $AlCl_{3}$

D) $PH_{3}$ and $SiCl_{4}$

Which of the following compounds contain(s) no covalent bond(s)?

KCl,PH₃,O₂,B₂H₆,H₂SO₄

A) $KCl,B_{2}H_{6},PH_{3}$

B) $KCl,H_{2}SO_{4}$

C) $KCl$

D) $KCl,B_{2}H_{6}$

Which of the following salts is the most basic in aqueous solution?

A) $Al(CN)_{3}$

B) $CH_{3}COOK$

C) $FeCl_{3}$

D) $Pb(CH_{3}COO)_{2}$

The compound that does not proudce nitrogen gas by the thermal decomposition is

A) $Ba(N_{3})_{2}$

B) $(NH_{4})_{2}Cr_{2}O_{7}$

C) $(NH_{4})_{2}SO_{4}$

D) $NH_{4}NO_{2}$

An aqueous solution contain unkonwn concentration of Ba^2+.When 50 mL of a 1M solutionof Na₂SO₄ is added , BaSO₄ just begins to precipitate. The final volume is 500 mL. The solubility product of BaSO₄ is 1×10^-10. What is the original concentration of Ba²⁺?

A) $5\times 10^{-9}M$

B) $2\times 10^{-9}M$

C) $1.1\times 10^{-9}M$

D) $1.0\times 10^{-10}M$

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

Based on the compounds of group 15 elements, the correct statement(s) is (are)

A) $Bi_{2}O_{5}$ is more basic than $N_{2}O_{5}$

B) $N_{}F_{3}$ is more covalent than $Bi_{}F_{3}$

C) $P_{}H_{3}$ boils at lower temperature than $N_{}H_{3}$

D) The N-N single bond is stronger than the P-P single bond

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

Galena (an ore) is partially oxidised by passing air through it at high temperature. After some time , the passage of air is stopped, but the heating is continued in a closed furnace such that the content undergo self- reduction. The weight (in kg)of Pb produced per kg of O₂ consumed is............ ( Atomic weights in g mol^-1 O= 16, S =32, Pb= 207)

A) 7.25kg

B) 5.26kg

C) 6.85kg

D) 6.47kg

To measure the quantity of Mncl₂ dissolved in an aqueous solution , it was completely converted to KMnO₄ using the reaction.

$MnCl_{2}+K_{2}S_{2}O_{8}+H_{2}O\rightarrow KMnO_{4}+H_{2}SO_{4}+HCl$

(equation not balanced)

Few drops of concentrated HCl were added to this solution and gently warmed. Further, oxalic acid (225 mg) was added in portions till the colour of the permanganatic ion disappeared. The quantity of MnCl₂ (in mg) present in the initial solution is........

[Atomic weights in g mol ^-1 : Mn =55, Cl= 35.5]

A) 128mg

B) 115mg

C) 126mg

D) 130mg

In the following reactions sequence, the amount of D (in gram) formed from 10 moles of acetophenone is ...........

(Atomic weights in g mol ^-1: H=1, C=12, N=14, O=16, Br= 80. The yield (%) corresponding to the product in each step is given in the parenthesis)

A) 495 g

B) 480 g

C) 525 g

D) 545 g

The surface of copper gets tarnished by the formation of copper oxide. N₂ gas was passed to prevent the oxide formation during heating of copper at 1250 K. However, the N₂ gas contains 1 mole % of water vapor as an impurity. The water vapor oxidizes copper as per the reaction is given below

$2Cu (g) + H_{2}O (g) \rightarrow Cu_{2}O (s)+H_{2}(g)$

$P_{H_{2}}$ is the minimum partial pressure of H₂ (in bar) needed to prevent the oxidation at 1250 K. The value of In $P_{H_{2}}$ is........

[Given : total pressure = 1 bar , R ( universal gas constant ) = 8 JK^-1 mol^-1, ln(10)=2.30 Cu(s) and Cu₂ O(s) are mutually immiscible.)

At 1250 K

$2 Cu (s)+\frac{1}{2}O_{2}(g)\rightarrow Cu_{2}O (s);$

$\triangle G^{\ominus} $=-78,000 J mol^-1

$H_{2}(g)+\frac{1}{2}O_{2}\rightarrow H_{2}O (g);$

$\triangle G^{\ominus}$ =-178,000 J mol^-1

G is the Gibs energy

A) -13.2

B) 13.2

C) 14.6

D) -14.6

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