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Which of the energy values marked as I, II and III in the following diagram, will change by the addition of a suitable catalyst?
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Which of the energy values marked as I, II and III in the following diagram, will change by the addition of a suitable catalyst?
The product 'X' in the following reaction is
At 298 K, change in internal energy for the complete combustion of fullerene, $$\text{C}_{60}(s)$$, an allotrope of carbon, and the enthalpy of formation of $$\text{CO}_2(g)$$ are $$-25970\ \text{kJ mol}^{-1}$$ and $$-393\ \text{kJ mol}^{-1}$$ respectively. The enthalpy of formation of $$\text{C}_{60}(s)$$ at 298 K is
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Which of the following is not paramagnetic?
Solubility product of AgCl is $$1.8 \times 10^{-10}$$. The minimum volume (in L) of water required to dissolve 1 mg of AgCl is close to
The complex $$[\text{M(en)(Br)}_2(\text{Cl})_2]$$ has two optical isomers. Their configurations can be represented as
A sample of water from a river was analyzed for the presence of metal ions and the observations were recorded as given below
The water sample is likely to contain
The lattice enthalpy and enthalpy of solution in water for solid NaCl are $$753\ \text{kJ mol}^{-1}$$ and $$5\ \text{kJ mol}^{-1}$$ respectively. If the solution enthalpies of $$\text{Na}^+$$ and $$\text{Cl}^-$$ are in the ratio $$6 \colon 5$$, the enthalpy of hydration of $$\text{Na}^+$$ ion is
The gaseous product obtained on reaction of $$\text{BF}_3$$ with LiH is
The equilibrium constant K for the reversible reaction $$A \rightleftharpoons B$$ is $$2 \times 10^3$$ at 350 K. The rate constants of the forward reaction in the presence and absence of a suitable catalyst at the same temperature are $$5 \times 10^4\ \text{s}^{-1}$$ and $$4 \times 10^{-6}\ \text{s}^{-1}$$ respectively. The rate constant of the reverse reaction in the absence of the catalyst is
The number of stereoisomers possible for the following compound
An adsorption isotherm equation proposed by Langmuir is of the form $$V = \frac{V_0 bP}{1 + bP}$$ where V is the volume of gas adsorbed at pressure P. For a given adsorbate or adsorbent system, $$V_0$$ and b are constants. The dependence of V on P can be depicted as
For the reaction $$4\text{NO}_2(g) + \text{O}_2(g) \to 2\text{N}_2\text{O}_5(g)$$, $$\Delta H_{reaction} = -112\ \text{kJ}$$. If the $$\text{N}_2\text{O}_5$$ is assumed to be formed in the reaction as a solid, $$\Delta H_{reaction}$$ will be (the enthalpy of sublimation of $$\text{N}_2\text{O}_5$$ is $$54\ \text{kJ mol}^{-1}$$)
Urea, $$\text{CO(NH}_2)_2$$, decomposes at $$90^\circ\text{C}$$ as $$\text{CO(NH}_2)_2(aq) \to \text{NH}_4^+(aq) + \text{OCN}^-(aq)$$. Experimental data obtained for the reaction is given in the following plot
From the graph it can be inferred that
If for an aqueous solution of a weak acid, $$pH = pK_a + 2$$ at $$25^\circ\text{C}$$, the approximate fraction of the acid in the dissociated form is
2.0 L of $$\text{N}_2$$ gas kept at $$25^\circ\text{C}$$ and 5 atm pressure were expanded isothermally against a constant pressure of 1 atm until the pressure of the gas reaches 1 atm. Assuming ideal behaviour, work of expansion in this process (in J) is close to
The compound which would undergo a reaction with ammonia by $$S_N1$$ mechanism is
The daily energy requirement of a teenager is 7800 kJ. As calculated from the data given in the table below, the amount of glucose he has to consume (g) per day assuming that the entire energy he requires comes from the combustion of glucose is
The pressure inside two gas cylinders of volume $$25\ \text{m}^3$$ and $$50\ \text{m}^3$$ are 10 kPa and 20 kPa respectively. The cylinders are kept at the same temperature and separated by a valve. What is the pressure in the combined system when the valve is opened?
Aluminium and copper are extracted from their oxide and sulphide ores respectively.
Which of the following is correct?
I. Copper is extracted by the auto reduction of copper oxide by copper sulphide.
II. Aluminium cannot be obtained by chemical reduction due to its strong affinity for oxygen.
III. In electrometallurgy of Al, graphite is used as cathode to avoid reoxidation of Al into $$\text{Al}_2\text{O}_3$$ by preventing formation of $$\text{O}_2$$.
IV. Sulphide ores of copper are difficult to be reduced than the oxide ores
Which of the following graphs describes the relationship between $$[\text{H}_3\text{O}^+]$$ and $$[\text{OH}^-]$$ in an aqueous solution at a constant temperature?
From the given standard electrode potentials
$$\text{Sn}^{4+}(aq) + 2e^- \to \text{Sn}^{2+}(aq)$$ $$E^0 = 0.15\ \text{V}$$ and $$\text{Br}_2(l) + 2e^- \to 2\text{Br}^-(aq)$$ with $$E^0 = 1.07\ \text{V}$$, the approximate free energy change for the process $$2\text{Br}^-(aq) + \text{Sn}^{4+}(aq) \to \text{Br}_2(l) + \text{Sn}^{2+}(aq)$$ is
Number of moles of $$\text{KClO}_3$$ that have to be heated to produce 1.0 L of $$\text{O}_2(g)$$ at STP can be expressed as
The sequence of reagents required for the following conversion is
Among the following, number of oxygen atoms present is the maximum in
Which of the following elements will exhibit photoelectric effect with light of the longest wavelength?
Compound 'X' in the following reaction is
The standard molar entropies of $$\text{H}_2(g)$$, $$\text{N}_2(g)$$ and $$\text{NH}_3(g)$$ are 130, 190 and $$193\ \text{J mol}^{-1}\text{K}^{-1}$$ respectively. For the reaction $$\frac{1}{2}\text{N}_2(g) + \frac{3}{2}\text{H}_2(g) \rightleftharpoons \text{NH}_3(g)$$ with $$\Delta H_{reaction} = -45\ \text{kJ}$$ to be in equilibrium, the temperature must be equal to
Density of $$\text{CO}_2$$ gas at $$0^\circ\text{C}$$ and 2.00 atm pressure can be expressed as
The maximum number of moles of $$\text{CH}_3\text{I}$$ consumed by one mole of crixivan, a drug used against AIDS is
Concentration of $$\text{K}^+$$ ions inside a biological cell was found to be 25 times higher than that outside. The magnitude of the potential difference between the two sides of the cell is close to (2.303 RT/F can be taken as 59 mV; difference in concentrations of other ions can be taken as negligible.)
The standard redox potential for the reaction $$2\text{H}_2\text{O} \to \text{O}_2 + 4\text{H}^+ + 4e^-$$ is $$-1.23\ \text{V}$$. If the same reaction is carried out at $$25^\circ\text{C}$$ and at pH 7, the potential will be
The order of $$pK_a$$ values of the following acids is
If the radius of the hydrogen atom is 53 pm, the radius of the $$\text{He}^+$$ ion is close to
A substance X was heated at constant pressure and the temperature observed at various times of heating was plotted as given below
Which of the following is or are correct?
I. Melting point of X is $$-5^\circ\text{C}$$.
II. Solid and liquid forms of X coexist in the region b.
III. Boiling point of X is $$55^\circ\text{C}$$.
IV. Solid and liquid forms of X coexist in the region d
The major product of the following reaction is
In which of the following, all the bond lengths are not the same? I. $$\text{IF}_4^+$$ II. $$\text{BF}_4^-$$ III. $$\text{SF}_4$$ IV. $$\text{TeCl}_4$$
Among the following, the reaction or reactions that can be classified as oxidation reduction is or are
I. $$\text{Cr}_2\text{O}_7^{2-}(aq) + 2\text{OH}^-(aq) \to 2\text{CrO}_4^{2-} + \text{H}_2\text{O}(l)$$
II. $$\text{SiCl}_4(l) + 2\text{Mg}(s) \to 2\text{MgCl}_2(l) + \text{Si}(s)$$
III. $$6\text{Cl}_2(l) + 12\text{KOH}(l) \to 2\text{KClO}_3(s) + 10\text{KCl} + 6\text{H}_2\text{O}(l)$$
IV. $$2\text{H}_2\text{O}_2 \to 2\text{H}_2\text{O}(l) + \text{O}_2(g)$$
Among the following pairs, the one in which both the compounds as pure liquids can show significant auto ionization is
The number of quaternary and chiral carbon atoms present in elatol, isolated from an algae are respectively
Compounds X ($$pK_a$$ about 15) and Y ($$pK_a$$ about 10), both produce $$\text{H}_2$$ on treatment with sodium metal and both yield a mixture of isomers on mononitration. X and Y respectively are
A crystal of KCl containing a small amount of $$\text{CaCl}_2$$ will have
In the following reaction, the values of a, b and c, respectively are
$$a\,\text{F}_2(g) + b\,\text{OH}^-(aq) \to c\,\text{F}^-(aq) + d\,\text{OF}_2(g) + e\,\text{H}_2\text{O}(l)$$
The monosaccharide present in the following disaccharide is
The IUPAC name of the complex $$[\text{Pt(en)(NH}_3)(\text{Cl})_2(\text{ONO})][\text{Ag(CN)}_2]$$ is
The correct order of basicity of the following species is
Which among the following is nonlinear?
The compound most likely to lose water on protonation is
The Newman projection shown is the same as
Which one of the following is not used as a monomer for the synthesis of a high molecular weight silicone polymer?
In $$\text{YBa}_2\text{Cu}_3\text{O}_{7-x}$$, a superconducting oxide that got George Bednorz and Karl Muller the Nobel prize in 1986, Cu can exist in both $$+2$$ and $$+3$$ oxidation states and their proportion depends on the value of x. In $$\text{YBa}_2\text{Cu}_3\text{O}_{6.5}$$
Compound 'Y' (molar mass $$88.12\ \text{g mol}^{-1}$$) containing 54.52 % carbon, 9.17 % hydrogen and 36.31% oxygen gives a reddish-brown precipitate in Fehling's test. 'Y' is
The IUPAC name of the following compound is
The correct order of boiling points of the following compounds is
Which of the following is a strong oxidising agent?
The molecule in which all atoms are not coplanar is
The most stable radical among the following is
During World War II, soldiers posted at high altitudes experienced crumbling of the tin buttons of their uniforms into a grey powder. This can be attributed to
The molecules that can exhibit tautomerism are
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A scientist attempts to replace a few carbon atoms in 1.0 g of diamond with boron atoms or nitrogen atoms in separate experiments. Which of the following is correct?
Compound 'P' that undergoes the sequence of reactions given below to give the product Q is
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The most stable Lewis structure of $$\text{N}_2\text{O}$$ is
The major product 'X' formed in the following reaction is
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Which of the following accounts best for the fact that $$\text{F}^-$$ is smaller than $$\text{O}^{2-}$$?
The correct sequence of reagents from those listed below for the following conversion is I. $$\text{NaNH}_2$$ II. $$\text{Br}_2$$ III. $$\text{H}_2$$ over Pd-C with quinoline IV. $$\text{H}_3\text{O}^+$$
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An orbital among the following that has two radial nodes and two angular nodes is
The compound 'X' undergoing the following reaction is
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A dilute solution of an alkali metal in liquid ammonia is I. blue in colour II. conducts electricity III. paramagnetic IV. an oxidising agent
The reactions from those given below that involve a carbocation intermediate are
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The C-O bond length is the shortest in
The rate of the reaction between two reactants X and Y can be expressed as $$R = k[X]^2[Y]$$. In an experiment, the initial rate of the reaction was found to be $$R_1$$ when the initial concentrations of X and Y are $$[X_0]$$ and $$[Y_0]$$. Another experiment was performed in which $$[X_0]$$ was taken as $$\frac{1}{2}[X_0]$$. What should be $$[Y_0]$$ in this experiment to get the initial rate as $$0.5R_1$$?
Among the following, the compound that has the highest dipole moment is
A common method to clean acid spills is to use $$\text{Na}_2\text{CO}_3$$ (Molar mass 106 g). If 50.0 mL of 0.75 M HCl is spilt on a wooden surface, the amount of $$\text{Na}_2\text{CO}_3$$ required is
The spin-only magnetic moments of $$[\text{Fe(NH}_3)_6]^{3+}$$ and $$[\text{FeF}_6]^{3-}$$ (in units of BM) respectively are
The major product of the following reaction is
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The standard electrode potential of the Daniel cell is 1.1 V and the overall cell reaction can be represented as $$\text{Zn}(s) + \text{Cu}^{2+}(aq) \to \text{Zn}^{2+}(aq) + \text{Cu}(s)$$. Under which of the following conditions will the cell potential be higher than 1.1 V?
Penicillamine is used in the treatment of arthritis. One molecule of penicillamine contains a single sulphur atom and the weight percentage of sulphur in penicillamine is 21.49%. Molecular weight of penicillamine in $$\text{g mol}^{-1}$$ is
An ion exchange resin, $$\text{RH}_2$$, can replace $$\text{Ca}^{2+}$$ in hard water as $$\text{RH}_2 + \text{Ca}^{2+} \to \text{RCa}^{2+} + 2\text{H}^+$$. When a 1.0 L hard water sample was passed through the resin, all $$\text{H}^+$$ ions were replaced by $$\text{Ca}^{2+}$$ ions and the pH of eluted water was found to be 2.0. The hardness of water (as ppm of $$\text{Ca}^{2+}$$) in the sample of water treated is
The analysis of three different binary oxides of bromine (Br) and oxygen (O) gives the following results
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Which of the following statements is not correct? I. Compound Y is $$\text{Br}_2\text{O}_3$$ II. Compound Z is $$\text{Br}_2\text{O}_5$$ III. Compound Z is $$\text{Br}_2\text{O}_7$$ IV. Compound Y is $$\text{Br}_2\text{O}_5$$
Which of the following statements is or are correct? I. Number of significant figures in 2345.100 is three II. 0.00787 rounded to two significant figures is written as $$0.787 \times 10^{-2}$$ III. 340 rounded to two significant figures is written as $$0.34 \times 10^3$$ IV. The number of significant figures in 0.020 is two
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