Recent questions tagged 2014

The most suitable reagent for the conversion of $R-CH_2- OH \to R - CHO$ is:

asked Dec 11, 2018 by pady_1

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For complete combustion of ethanol, $C_2H_5OH (\ell) + 3O_2 (g) \to 2CO_2 (g) + 3H_2O (\ell)$, the amount of heat produced as measured in bomb calorimeter, is $1364.47\; kJ \;mol^{–1}$ at $25^{\circ}C$. Assuming ideality the Enthalpy of combustion, $\Delta_CH$, for the reaction will be: $(R = 8.314\; kJ \;mol^{–1} )$

asked Dec 11, 2018 by pady_1

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Among the following oxoacids, the correct decreasing order of acid strength is:

asked Dec 11, 2018 by pady_1

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Which one is classified as a condensation polymer?

asked Dec 11, 2018 by pady_1

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The ratio of masses of oxygen and nitrogen in a particular gaseous mixture is 1 : 4. The ratio of number of their molecule is:

asked Dec 11, 2018 by pady_1

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Given below are the half-cell reactions : $Mn^{2+} + 2e^- \to Mn; \; E^0 = -1.18 \;V$ $2(Mn^{3+} + e^- \to Mn^{2+} ) \; ; E^0 = +1.51 \; V$ The $E^0$ for $2Mn^{2+} \to Mn + 2Mn^{3+} $ will be :

asked Dec 11, 2018 by pady_1

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The major organic compound formed by the reaction of 1, 1, 1-trichloroethane with silver powder is :

asked Dec 11, 2018 by pady_1

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The correct set of four quantum numbers for the valence elections of rubidium atom (Z= 37) is:

asked Dec 11, 2018 by pady_1

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Which one of the following bases is not present in DNA?

asked Dec 11, 2018 by pady_1

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Considering the basic strength of amines in aqueous solution, which one has the smallest $pK_b$ value?

asked Dec 11, 2018 by pady_1

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Which series of reactions correctly represents chemical reactions related to iron and its compound?

asked Dec 11, 2018 by pady_1

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For the non â€“ stoichiometre reaction $2A +B \to C + D$ , the following kinetic data were obtained in three separate experiments, all at $298\; K$. The rate law for the formation of C is:

asked Dec 11, 2018 by pady_1

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For which of the following molecule significant $\mu \neq 0$?

asked Dec 11, 2018 by pady_1

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The equation which is balanced and represents the correct product(s) is:

asked Dec 11, 2018 by pady_1

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The correct statement for the molecule, $CsI_3$ is:

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On heating an aliphatic primary amine with chloroform and ethanolic potassium hydroxide, the organic compound formed is:

asked Dec 11, 2018 by pady_1

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Sodium phenoxide when heated with $CO_2$ under pressure at $125^{\circ}C$ yields a product which on acetylation produces $C$. The major product C would be:

asked Dec 11, 2018 by pady_1

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In the reaction, $CH_3COOH \xrightarrow{LiAlH_4} A \xrightarrow{PCl_5} B \xrightarrow{Alc. KOH} C$, the product C is :

asked Dec 11, 2018 by pady_1

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For the reaction, $SO_{2(g)} + \frac{1}{2}O_{2(g)} \leftrightharpoons SO_{3(g)}$, if $K_P = K_C(RT)^x$ where the symbols have usual meaning then the value of $x$ is: (assuming ideality)

asked Dec 11, 2018 by pady_1

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The equivalent conductance of NaCl at concentration C and at infinite dilution are $\lambda_C$ and $\lambda_{\infty}$, respectively. The correct relationship between $\lambda_C$ and $\lambda_{\infty}$ is given as: (where the constant B is positive)

asked Dec 11, 2018 by pady_1

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For the estimation of nitrogen, $1.4\; g$ of organic compound was digested by Kjeldahl method and the evolved ammonia was absorbed in $60 \;mL$ of $\frac{M}{10}$ sulphuric acid. The unreacted acid require$20\; ml$ of $\frac{M}{10}$ sodium hydroxide for complete neutralization. The percentage of nitrogen in the compound is:

asked Dec 11, 2018 by pady_1

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The octahedral complex of a metal ion $M^{3+}$ with four monodentate ligands $L_1, L_2, L_3$ and $L_4$ absorb wavelengths in the region of red, green, yellow and blue, respectively. The increasing order of ligand strength of the four ligands is:

asked Dec 11, 2018 by pady_1

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In $S_N2$ reactions, the correct order of reactivity for the following compounds: $CH_3Cl, \;CH_3CH_2Cl,\; (CH_3)_2CHCl$ and $(CH_3)_3CCl$ is:

asked Dec 11, 2018 by pady_1

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In which of the following reactions $H_2O_2$ acts as a reducing agent? (a) $H_2O_2 +2H^+ + 2e^- \to 2H_2O$ (b) $H_2O_2 - 2e^- \to O_2 + 2H^+$ (c) $H_2O_2 + 2e^- \to 2OH^- $ (d) $H_2O_2 + 2OH^- - 2e^- \to O_2 + 2H_2O$

asked Dec 11, 2018 by pady_1

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Consider separate solutions of $0.500\; M\; C_2H_5OH(aq),\; 0.100\; M \;Mg_3(PO_4)_2(aq),\; 0.250\; M\; KBr(aq)$ and $0.125 \;M \;Na_3PO_4(aq)$ at $25^{\circ}C$. Which statement is true about these solutions, assuming all salts to be strong electrolytes?

asked Dec 11, 2018 by pady_1

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CsCl crystallises in body centred cubic lattice. If ‘a’ is its edge length then which of the following expressions is correct?

asked Dec 11, 2018 by pady_1

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Resistance of $0.2\; M$ solution of an electrolyte is $50 \Omega$. The specific conductance of the solution is $1.4 \;S m^{-1}$ . The resistance of $0.5\; M$ solution of the same electrolyte is $280 \Omega$. The molar conductivity of $0.5\; M$ solution of the electrolyte in $S \;m^2 mol^{-1}$ is:

asked Dec 11, 2018 by pady_1

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The metal that cannot be obtained by electrolysis of an aqueous solution of its salts is:

asked Dec 11, 2018 by pady_1

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If Z is a compressibility factor, van der Waals equation at low pressure can be written as:

asked Dec 11, 2018 by pady_1

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Which one of the following properties is not shown by NO?

asked Dec 11, 2018 by pady_1

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If $x = -1$ and $x = 2$ are extreme points of $f(x) = \alpha \log |x| + \beta x^2 + x$, then

asked Dec 11, 2018 by pady_1

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The slope of the line touching both the parabolas $y^2 = 4x$ and $x^2 = -32y$ is

asked Dec 11, 2018 by pady_1

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The angle between the lines whose direction cosines satisfy the equations $l + m + n = 0$ and $l^2 = m^2 + n^2$ is

asked Dec 11, 2018 by pady_1

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If $(10)^9 + 2(11)^1 (10)^8 + 3(11)^2 (10)^7 + ....+ 10(11)^9 = k(10)^9$, then $k$ is equal to

asked Dec 11, 2018 by pady_1

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Three positive numbers from an increasing G.P. If the middle term in this G.P. is doubled, the new numbers are in A.P. Then the common ratio of the G.P. is

asked Dec 11, 2018 by pady_1

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The locus of the foot of perpendicular drawn from the centre of the ellipse $x^2 + 3y^2 = 6$ on any tangent to it is

asked Dec 11, 2018 by pady_1

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If $X = \{4^n - 3n - 1 : n \in N\}$ and $Y = \{9(n - 1) : n \in N\}$, where $N$ is the set of natural numbers, then $X \cup Y$ is equal to

asked Dec 11, 2018 by pady_1

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$\displaystyle{\lim_{x \to 0} \frac{\sin( \pi \cos^2 x)} {x^2}}$ is equal to

asked Dec 11, 2018 by pady_1

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Let PS be the median of the triangle with vertices $P(2, 2), Q(6, -1)$ and $R(7, 3)$. The equation of the line passing through $(1, -1)$ and parallel to PS is

asked Dec 11, 2018 by pady_1

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Let $a, b, c$ and d be non-zero numbers. If the point of intersection of the lines $4ax + 2ay + c = 0$ and $5bx + 2by + d = 0$ lies in the fourth quadrant and is equidistant from the two axes then

asked Dec 11, 2018 by pady_1

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The area of the region described by $A = \{(x, y) : x^2 + y^2 \leq 1$ and $y^2 \leq 1 - x\}$ is

asked Dec 11, 2018 by pady_1

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Let C be the circle with centre at $(1, 1)$ and $radius = 1$. If T is the circle centred at $(0, y)$, passing through origin and touching the circle C externally, then the radius of T is equal to

asked Dec 11, 2018 by pady_1

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Let the population of rabbits surviving at a time t be governed by the differential equation $\frac{dp(t)}{dt} = \frac{1}{2} p(t) - 200$ . If $p(0) = 100$, then $p(t)$ equals

asked Dec 11, 2018 by pady_1

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If f and g are differentiable functions in $[0, 1]$ satisfying $f(0) = 2 = g(1), g(0) = 0 $ and $f(1) = 6$, then for some $c \in ]0, 1[$

asked Dec 11, 2018 by pady_1

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et A and B be two events such that $P (\overline{A \cup B}) = \frac{1}{6} , \; P ( A \cap B) = \frac{1}{4} $ and $P(\overline{A}) = \frac{1}{4}$ , where $\overline{A}$ stands for the complement of the event A. Then the events A and B are

asked Dec 11, 2018 by pady_1

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Let $\alpha$ and $\beta$ be the roots of equation $px^2 + qx + r = 0,\; p \neq 0$. If $p, q, r$ are in A.P. and $\frac{1}{\alpha} + \frac{1}{\beta} = 4$, then the value of $|\alpha - \beta|$ is

asked Dec 11, 2018 by pady_1

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Let $f_K(x) = \frac{1}{k} (\sin^k x + \cos^k x)$ where $x \in R$ and $k \geq 1$. Then $f_4(x) - f_6(x)$ equals

asked Dec 11, 2018 by pady_1

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If $\alpha, \beta \neq 0$, and $f(n) = \alpha^n + \beta^n$ and $ \begin{vmatrix} 3 & 1+f(1) & 1+f(2) \\ 1+f(1) & 1+f(2) & 1+f(3) \\ 1+f(2) & 1+f(3) &1+f(4) \end{vmatrix} = K(1 - \alpha)^2 (1 - \beta)^2 (\alpha - \beta)^2$, then $K$ is equal to

asked Dec 11, 2018 by pady_1

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If $g$ is the inverse of a function $f$ and $f'(x) = \frac{1}{1+x^5}$ , then $g'(x)$ is equal to

asked Dec 11, 2018 by pady_1

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If z is a complex number such that $|z| \geq 2$, then the minimum value of $| x + \frac{1}{2} |$

asked Dec 11, 2018 by pady_1

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