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If $\overrightarrow{a} = \hat{i} + 4 \hat{j}, \; \overrightarrow{b} = 2 \hat{i} - 3 \hat{j}, \; \overrightarrow{c} = 5 \hat{i} + 9 \hat{j}$ , then $\overrightarrow{c}$ is equal to :

asked Dec 11, 2018 by pady_1

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How many litres of oxygen (at STP) are required for complete ccombustion of 39 g of liquid benzene ? (Atomic weights : C = 12, O = 16, H = 1 )

asked Dec 11, 2018 by pady_1

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Consider the following reaction : $A \to products$ This reaction is completed in 100 minutes. The rate constant of this reaction at $t_1 =10\; min$ , is $10^{-2} \;min^{-1}$ . What is the rate constant (in $min^{-1}$ ) at $t_2 = 20$ minutes ?

asked Dec 11, 2018 by pady_1

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Equilibrium constant for the reaction $H_2O(g) + CO (g) \leftrightharpoons H_2(g) + CO_2 (g)$ is 81. If the velocity constant of the forward reaction is $162\; L\; mol^{-1} s^{-1}$ . What is the velocity constant (in $L\;mol^{-1} s^{-1}$ ) for the backward reaction ?

asked Dec 11, 2018 by pady_1

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Molten $CuCl_2$ is electrolysed using platinum electrodes. The reaction occuring at anode is :

asked Dec 11, 2018 by pady_1

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One ampere of current is passed for 9650 seconds through molten $AlCl_3$ . What is the weight in grams of $Al$ deosited at cathode ? (atomic weight of Al = 27)

asked Dec 11, 2018 by pady_1

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Which of the following would produce a buffer solution when mixed in equal volumes ?

asked Dec 11, 2018 by pady_1

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The $pK_a$ of a weak acid is $4.8$ . What should be the ratio of $\frac{[acid]}{[salt]}$ , if a buffer of $pH = 5.8$ is required ?

asked Dec 11, 2018 by pady_1

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250 mL of a sodium carbonate solution contains 2.65 g of $Na_2CO_3$ . If 10 mL of this solution is diluted to one litre, what is the concentration of the resultant solution ?

asked Dec 11, 2018 by pady_1

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$n$ moles of an ideal gas at temperature $T$ (in kelvin) occupy $V\; L$ of volume, exerting a pressure of $P$ atmospheres. What is the concentration (in $mol/L$ ) ?

asked Dec 11, 2018 by pady_1

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The r.m.s velocity of $CO_2$ at a temperature $T$ (in kelvin) is $x\; cm\;sec^{-1}$ . At what temperature (in kelvin), the r.m.s. velocity of nitrous oxide would be $4x\;cm\;sec^{-1}$ ? (Atomic weights of $C, \; N$ and $O$ are respectively $12, \; 14$ and $16$ ) :

asked Dec 11, 2018 by pady_1

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What are the oxidation numbers of nitrogen in $NH_4NO_3$ ?

asked Dec 11, 2018 by pady_1

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What is the volume (in litres) of oxygen at STP required for complete combustion of 32 g of $CH_4$ ? (Molecular weight of $CH_4$ is 16)

asked Dec 11, 2018 by pady_1

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Bond dissociation energies of $HF, \; HCl,\; HBr$ follow the order .....

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Which of the following statements is true ?

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The element with atomic number 12 belongs to .......... group and ............. period :

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Let electronegativity, ionisation energy and electron affinity be represented as EN, IP and EA respectively. Which one of the following equation is correct according to Mulliken ?

asked Dec 11, 2018 by pady_1

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What is X in the following reaction $_{12}Mg^{26} + _1H^2 \to _{12}Mg^{27}$ + X$ :

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In a nuclide, one a.m.u of mass is dissipated into energy to bind its nucleons. The energy equivalent of this mass is :

asked Dec 11, 2018 by pady_1

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In the ground state, an element has 13 electrons in M shell. The element is :

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The energy of an electron present in Bohr's second orbit of hydrogen atom is :

asked Dec 11, 2018 by pady_1

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The metal ion present in vitamin $B_{12}$ is :

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Consider the following reaction : $C_6H_5NO_2 \xrightarrow{Sn/HCl} X \xrightarrow{C_6H_5COCl} Y + HCl$ What is $Y$ ?

asked Dec 11, 2018 by pady_1

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Aceic acid is reacted with metallic sodium to form hyrdogen and X. When X is heated with sodalime, Y and sodium carbonate are formed. Y is ......... ?

asked Dec 11, 2018 by pady_1

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When acetaldehyde is reacted with $LiAlH_4$ , whar is the product formed ?

asked Dec 11, 2018 by pady_1

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Dry distillation of calcium acetate and calcium formate forms :

asked Dec 11, 2018 by pady_1

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What is $Y$ in the following reaction ? $C_2H_5I + NaOC_2H_5 \to X + NaI$ $X + 2HI \xrightarrow{\Delta} 2Y + H_2O$

asked Dec 11, 2018 by pady_1

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Absolute alcohol (100% alcohol) is prepared by distilled rectified spirit over :

asked Dec 11, 2018 by pady_1

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3 moles of ethanol reacts with one mole of phosphorus tribromide to form 3 moles of bromo-ethane and one mole of X. Which of the following is X ?

asked Dec 11, 2018 by pady_1

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Chloroethane reacts with $X$ to form diethyl ether. What is $X$ ?

asked Dec 11, 2018 by pady_1

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Ethanol, when reacted with $PCl_5$ gave $A$ , $POCl_3$ and $HCl$ . A reacts with silver nitrate to form $B$ ( major product) and $AgCl$ . $A$ and $B$ are respectively :

asked Dec 11, 2018 by pady_1

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Which one of the following is used in the preparation of styrene ?

asked Dec 11, 2018 by pady_1

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Consider the following reactions $C_2H_2 \xrightarrow[\text{500$^{\circ}$C}]{\text{red hot iron tube}} A$ $A \xrightarrow[\text{70$^{\circ}$C}]{\text{conc. $HNO_3$, conc. $H_2SO_4$}} B$ $B \xrightarrow{LiAlH_4} C_6H_5 - N = N - C_6H_5$ A and B are :

asked Dec 11, 2018 by pady_1

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Which one of the following pairs of compounds are functional isomers ?

asked Dec 11, 2018 by pady_1

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The structural formula 2-methyl-2-butene is :

asked Dec 11, 2018 by pady_1

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Which one of the following is mainly responsible for depletion of ozone layer ?

asked Dec 11, 2018 by pady_1

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Which one of the following ions exhibits highest magnetic moment ?

asked Dec 11, 2018 by pady_1

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The number of Ione pairs of electrons present on $Xe$ in $XeF_4$ is :

asked Dec 11, 2018 by pady_1

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Which one of the following halogen liberated oxygen, when passed through hot concentrated KOH solution ?

asked Dec 11, 2018 by pady_1

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Which one of the following order is correct for the bond energies of halogen molecules ?

asked Dec 11, 2018 by pady_1

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What are the products formed when chlorine is passed through aqueous hypo solution ?

asked Dec 11, 2018 by pady_1

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What are the products obtained when ammonia is reacted with excess chlorine ?

asked Dec 11, 2018 by pady_1

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Ionic radius (in $\mathring{A}$ ) of $As^{3+}, \; Sb^{3+}$ and $Bi^{3+}$ follow the order :

asked Dec 11, 2018 by pady_1

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The catenation tendency of $C, Si$ and $Ge$ is in the order $Ge < Si < C$ . The bond energies (in $kJ\; mol^{-1}$ ) of $C-C, \; Si-Si$ and $Ge-Ge$ bonds, respectively are :

asked Dec 11, 2018 by pady_1

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What is the molecular formula of borazole ?

asked Dec 11, 2018 by pady_1

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During the electrolytic reduction of alumina, the reaction at cathode is :

asked Dec 11, 2018 by pady_1

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In organic reactions, sodium in liquid ammonia is used as :

asked Dec 11, 2018 by pady_1

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The electronic configuration of elements A, B and C are $[He]2s^1, [Ne] 3s^1$ and $[Ar] 4s^1$ respectively, which one of the following order is correct for the first ionization potentials (in $k.J.\; mol^{-1}$ ) of A, B and C ?

asked Dec 11, 2018 by pady_1

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......... process is used for the removal of hardness of water :

asked Dec 11, 2018 by pady_1

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In which of the following reactions, $H_2O_2$ acts as a reducing reagents ?

asked Dec 11, 2018 by pady_1

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