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The results obtained by four students, each performing a set of four titrations with the same solution under identical conditions, are given below. If the expected titre value is 20.0 mL, the set of data (mL) with good accuracy and poor precision is
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The results obtained by four students, each performing a set of four titrations with the same solution under identical conditions, are given below. If the expected titre value is 20.0 mL, the set of data (mL) with good accuracy and poor precision is
The statement that is NOT correct about atomic spectra is
A closed 2.0 L container initially holds 3.0 mol of $$\text{O}_2$$ (g) and 2.0 mol of $$\text{N}_2$$ (g) at room temperature, T. If the pressure remains constant when 1.0 mol of $$\text{O}_2$$ (g) is added, the final temperature of the system is (assume ideal gas behaviour throughout)
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The equilibrium constant $$K_c$$ for trimerization of phenyl acetylene to triphenyl benzene is 3.0 at 310 K. If at equilibrium 0.9 mol $$\text{dm}^{-3}$$ of triphenyl benzene is present, concentration of phenyl acetylene at equilibrium is
At 298 K, the standard free energies of formation of cis- and trans-1,2-dichloroethene are 41.549 kJ and 33.235 kJ respectively. The most appropriate mol ratio of trans- and cis- isomers at equilibrium at 298 K is
The pH of the solution produced by complete consumption of 10 mL of 0.4 M NaOH to 'x' mL of 0.5 M $$\text{CH}_3\text{COOH}$$ was found to be 4.57. The value of 'x' (mL) is, given that $$K_a$$ of $$\text{CH}_3\text{COOH} = 1.8 \times 10^{-5}$$
The correct order of concentrations of the ions and molecules present in 1.0 L of 1.0 M $$\text{H}_2\text{SO}_4$$ (aq) solution is
The pOH of the solution obtained by mixing 30 mL of a strong monobasic acid of pH 3.0 and 70 mL of a strong monoacidic base of pH 12.0 at 298 K is
If refractive index, density, pressure, volume, heat capacity and surface tension are represented respectively as $$\eta$$, $$\rho$$, P, V, Q and $$\gamma$$, the set that contains only intensive properties is
Heat of reaction and heat of formation will be the same in
I. $$\frac{1}{2}\text{N}_2(g) + \text{O}_2(g) \rightarrow \text{NO}_2(g)$$,
II. $$\text{Xe}(g) + 2\text{F}_2(g) \rightarrow \text{XeF}_4(g)$$,
III. $$\text{N}_2(g) + \text{O}_3(g) \rightarrow \text{N}_2\text{O}_3(g)$$,
IV. $$\text{C (diamond)} + \text{O}_2(g) \rightarrow \text{CO}_2(g)$$
From the data $$2\text{CH}_6\text{N}_2(l) + 5\text{O}_2(g) \rightarrow 2\text{N}_2(g) + 2\text{CO}_2(g) + 6\text{H}_2\text{O}(g)$$ with $$\Delta H = -2606$$ kJ, and $$\text{H}_2\text{O}(l) \rightarrow \text{H}_2\text{O}(g)$$ with $$\Delta H = 44$$ kJ $$\text{mol}^{-1}$$, heat of combustion of $$\text{CH}_6\text{N}_2$$ at 298 K can be calculated as
When 100 g each of the salts NaCl, $$\text{MgSO}_4$$, $$\text{Ca(NO}_3)_2$$ and $$\text{K}_2\text{CO}_3$$ were dissolved separately in 1.0 kg of water, the solution with the highest boiling point will be of
When the pH of the system is increased by 2.0 units, maximum decrease in half cell potential for the reaction will be observed in
The reaction that takes place during charging of the lead storage cell is $$2\text{PbSO}_4(s) + 2\text{H}_2\text{O}(l) \rightarrow \text{Pb}(s) + \text{PbO}_2(s) + 2\text{H}_2\text{SO}_4(aq)$$. If a current of 10.0 A is passed for 1.50 h for charging, the amount of $$\text{PbSO}_4$$ reacted is
A sample of water from a water tank has a resistance of 100 $$\Omega$$ at 298 K, when placed in a conductivity cell of cell constant 0.2 $$\text{m}^{-1}$$. On dissolving 58.5 g of NaCl in the water tank, a sample of this solution gave a resistance of 40 $$\Omega$$. The molar conductivity of NaCl at this concentration is 10 $$\Omega^{-1}\text{m}^2\text{mol}^{-1}$$. The volume of water in the water tank is
Initial concentrations of the reactants and the corresponding half-lives for the reaction $$\text{P} + \text{Q} \rightarrow \text{R}$$ are given below. The rate law for the reaction is
The unit cell structure of a mineral perovskite crystallizes in cubic unit cell wherein calcium (filled circles) and oxide (hollow circles) constitute a cubic close packing (ccp) arrangement and titanium ion (hollow square) occupies an interstitial hole as shown below. Charges are omitted for simplicity. The empirical formula of this compound is
Study the sequence of reactions of diborane $$\text{B}_2\text{H}_6$$ given below and identify the products K, L, M and N. The shown reagents are taken in excess.
During extraction of gold, the gold ore is treated with aqueous KCN solution as shown by the equations, which are not balanced, to get compound X which is further reduced by Zn to obtain compound Y and metallic gold. The steps are gold ore $$+ \text{CN}^- + \text{H}_2\text{O} + \text{O}_2 \rightarrow [\text{X}] + \text{OH}^-$$ and $$[\text{X}] + \text{Zn} \rightarrow [\text{Y}] + \text{Au}$$. Identify X and Y.
The correct IUPAC name for the complex $$[\text{Au(en)}_2(\text{H}_2\text{O})_2][\text{Au(ox)}_3]$$, where en is ethylenediamine and ox is oxalate, is
Addition of dil. HCl to an aqueous solution of a mixture of two inorganic salts yielded white precipitate E and filtrate F. Precipitate E dissolved in hot water. F in alkaline alizarin gives a positive red lake test. The cations present in the precipitate E and solution F respectively are
$$\text{Br}_2$$ disproportionates to $$\text{Br}^-$$ and $$\text{BrO}_3^-$$ in a hot alkaline solution as $$3\text{Br}_2 + 6\text{OH}^- \rightarrow 5\text{Br}^- + \text{BrO}_3^- + 3\text{H}_2\text{O}$$. The equivalent weight of $$\text{Br}_2$$, where M is the molar mass of $$\text{Br}_2$$, is
The number of all the possible geometrical isomers for the trigonal bipyramidal $$\text{OsO}_2\text{F}_3^+$$ cation is
The correct order for the wavelength of absorption in the following complex ions is
Mixing of an aqueous salt solution containing nitrate ion with ferrous ion followed by gentle addition of conc. sulphuric acid from the sides of the test tube results in brown coloration at the interface. This is due to
Aqueous solutions of hydrogen sulphide and sulphur dioxide when mixed together give
The ion with least coagulation value for arsenous sulphide sol is
The correct order of catenation property among the following is
An agriculturist wants to use different concentrations of phosphorus as a fertilizer using $$\text{P}_4\text{O}_{10}$$. The correct expression to calculate P from $$\text{P}_4\text{O}_{10}$$ is
Given below are some names of the compounds. (p) Acetals, (q) silicones, (r) ferrocene, (s) glyoxal, (t) ethyl acetate, (u) gammaxene. The set which is NOT having a double bond between an element and O, that is $$\text{E} = \text{O}$$ where E is any element in the periodic table, as a functional group is
Hybridization of S in $$\text{CH}_3\text{SH}$$ molecule is
Using different reaction conditions nickel reacts with (p) $$\text{Cl}^-$$, (q) $$\text{CN}^-$$, (r) CO and (s) a small amount of Al. Choose the incorrect statement.
Optically pure 2-butanol has a specific rotation of $$+13.52$$ degrees. A synthesized and purified sample of 2-butanol has the observed specific rotation of $$+6.76$$ degrees. The correct statement based on this observation is
Certain organic reactions proceed through formation of intermediates which are highly strained and reactive. Given the following reaction, the correct statement about the mechanism of the reaction is
Which of the following compounds is NOT named correctly according to the IUPAC nomenclature?
Which of the following compounds contains the maximum number of $$sp^2$$ hybridized carbon atoms?
The number of products from the following, which cannot be formed on nitration of 1, 3-dichlorobenzene with a mixture of concentrated nitric acid and sulfuric acid is
Optically pure 3-Phenyl-2-butanone (X) with the following structure is treated with methyl magnesium iodide in anhydrous ether. The product formed after acidic hydrolysis is
Aldehydes react with carbonyl compounds in the presence of bases by a mechanism similar to aldol condensation. Given below is the reaction of benzaldehyde with 3-methyl-2-butanone in the presence of lithium diisopropylamide (LDA), a strong bulky base, and triethyl amine (TEA), a weak base. The correct structures of the major products, I and II formed in the following reactions are respectively
The correct order of the given reagents to convert benzene to m-Chlorobromobenzene is
A chiral hydrocarbon of molecular formula $$\text{C}_6\text{H}_{12}$$ undergoes catalytic hydrogenation to yield an achiral product of molecular formula $$\text{C}_6\text{H}_{14}$$. The chiral hydrocarbon is
The structure of multistriatin, a pheromone of the elm bark beetle, is shown beside. The open chain ketodiol that on dehydrative cyclization gives multistriatin, a bicyclic ketal, ignoring stereochemical aspects, is
A monobasic acid (0.100 g) on complete combustion gave 0.252 g of $$\text{CO}_2$$ and 0.044 g of $$\text{H}_2\text{O}$$. For complete neutralization of 0.122 g of the acid, 10.0 mL of 0.1 M NaOH solution was required. Molecular formula of the acid is
Acidity of acidic compounds depend on the stability of their conjugate bases. The correct order of acidity of the underlined H in the following compounds, assuming that all the compounds exist in the keto form, is
Reaction of para-Chloroaniline with acetic anhydride in pyridine gave a crude mixture of 94% of para-chloroacetanilide and 6% unreacted amine. From the following, the best treatment suitable for purification of para-chloroacetanilide is
3-tert-butylphenol when reacted separately with excess chlorine, bromine and iodine gave trichloro, di-bromo and mono-iodo derivatives of 3-tert-butylphenol respectively. The correct structures of the respective halogen derivatives are
Consider the following sequence of reactions, in which compound D has the formula $$\text{C}_3\text{H}_9\text{N}$$ and compound E has the formula $$\text{C}_3\text{H}_8\text{O}$$. The functional groups undergoing change in the conversion of A to E respectively are
The correct sequence of reagents which would convert p-Nitrotoluene to p-Iodobenzoic acid is
Following is a qualitative plot that can represent kinetic data obtained with a reactant R where $$[\text{R}]_0$$ and $$[\text{R}]$$ represent the concentrations of R at $$t = 0$$ and $$t = t$$ respectively. 'Y' and 'X' are suitable parameters on the x- and y- axes. The correct representation of the curve is
A given amount of an ideal gas undergoes the cyclic process ABCA as given below.
The equivalent representation or representations of the same process is or are
The correct statements among the following is or are
For the phenomenon of adsorption, the correct statement or statements among the following is or are
When excess $$\text{KMnO}_4$$ is added to concentrated $$\text{H}_2\text{SO}_4$$, an oily green colored covalent compound Y is formed. Which of the following statements is or are true for the above reaction?
Read carefully all the three statements on defects in solids.
(i) In Frenkel defect, interstitial $$\text{Ag}^+$$ site is surrounded tetrahedrally by four $$\text{Cl}^-$$ ions and four $$\text{Ag}^+$$ ions, where the interstitial $$\text{Ag}^+$$ and $$\text{Cl}^-$$ interaction is covalent.
(ii) Addition of small amount of $$\text{SrCl}_2$$ in NaCl yields solid solution with a formula of $$\text{Na}_{1-2x}\text{Sr}_x\text{V}_{\text{Na},x}\text{Cl}$$, where V is valency.
(iii) In general, Schottky defect increases the density of the substance.
Choose the correct alternative or alternatives.
Eriochrome black T (EBT) is an indicator in titrimetric estimation of calcium at pH 10.0 giving pink colour to the solution. It has the structure shown below, with $$pK_{a2} = 6.3$$ and $$pK_{a3} = 11.5$$. Considering that the pH of solution is 10.0, which statement or statements describe the complexation of EBT with Ca(II) correctly?
The correct statement or statements regarding the three $$\text{EI}_3$$ molecules, where E is P, As or Sb, is or are
Aldehydes and ketones can react with water in the presence of an acid or base to yield an equilibrium mixture of the aldehyde or ketone and the corresponding hydrates, the geminal diols. Among the following, the aldehydes and ketones which will have a greater percentage of the hydrate at equilibrium are
The correct statement or statements about the pyranose form of a sugar (X) given below is or are
Given below are isomeric amines. The incorrect statement or statements about them from the following is or are
Which one or ones of the reduction techniques mentioned below is or are NOT suitable for the following chemical transformation
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