Chemistry

Glycogen is a branched-chain polymer of α-D-glucose units in which chain is formed by C1—C4 glycosidic linkage whereas branching occurs by the formation of C1-C6 glycosidic linkage. Structure of glycogen is similar to __________.
(i) Amylose
(ii) Amylopectin
(iii) Cellulose
(iv) Glucose

Option (ii) is the answer. Glycogen has a similar structure to amylopeptin. It's an a-D glucose unit branched chain polymer with C1-C4 glycosidic linkage for chain formation and C1-C6 glycosidic...

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Proteins are found to have two different types of secondary structures viz. α-helix and β-pleated sheet structure. α-helix structure of the protein is stabilised by : (i) Peptide bonds (ii) van der Waals forces (iii) Hydrogen bonds (iv) Dipole-dipole interactions

Option ( iii) is the answer. Hydrogen bonding help to keep the -helix structure of proteins stable. By twisting into a right-handed helix and hydrogen bonding the -NH group of each amino acid...

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Which of the following reactions of glucose can be explained only by its cyclic structure?
(i) Glucose forms pentaacetate.
(ii) Glucose reacts with hydroxylamine to form an oxime.
(iii) Pentaacetate of glucose does not react with hydroxylamine.
(iv) Glucose is oxidised by nitric acid to gluconic acid

Option (iii) is the answer. The absence of a free -CHO group is indicated by the fact that glucose pentaacetate does not react with hydroxylamine. Only the cyclic nature of glucose may explain this...

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Structure of a disaccharide formed by glucose and fructose is given below. Identify anomeric carbon atoms in monosaccharide units.
(i) ‘a’ carbon of glucose and ‘a’ carbon of fructose.
(ii) ‘a’ carbon of glucose and ‘e’ carbon of fructose.
(iii) ‘a’ carbon of glucose and ‘b’ carbon of fructose.
(iv) ‘f’ carbon of glucose and ‘f ’ carbon of fructose.

Option (iii) is the answer. Anomeric carbon is carbon that is next to an oxygen atom in the cyclic structure of glucose or fructose. 'a' and 'b' are next to the oxygen atom, as illustrated in the...

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Three structures are given below in which two glucose units are linked. Which of these linkages between glucose, units are between C1 and C4 and which linkages are between C1 and C6?
(i) (A) is between C1 and C4, (B) and (C) is between C1 and C6
(ii) (A) and (B) are between C1 and C4, (C) is between C1 and C6
(iii) (A) and (C) is between C1 and C4, (B) is between C1 and C6
(iv) (A) and (C) is between C1 and C6, (B) is between C1 and C4

Option (iii) is the answer (A) and (C) are in the Cl-C4 range, while (B) is in the Cl-C6 range.

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In nucleoside, a base is attached at 1C position of the sugar moiety. A nucleotide is formed by linking the phosphoric acid unit to the sugar unit of a nucleoside. At which position of sugar unit is the phosphoric acid linked in a nucleoside to give a nucleotide?

When a nitrogenous base is connected to the 1' position of a five-carbon sugar, a nucleoside is produced. The 5' carbon of the sugar in a nucleoside molecule is bonded to the 5' carbon of the sugar...

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The letters ‘D’ or ‘L’ before the name of a stereoisomer of a compound indicates the correlation of configuration of that particular stereoisomer. This refers to their relationship with one of the isomers of glyceraldehyde. Predict whether the following compound has ‘D’ or ‘L’ configuration.

On the left side of the C5 carbon atom, the –OH group is connected. As a result, the provided compound is in the 'L' configuration.

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Protein found in a biological system with a unique three-dimensional structure and biological activity is called a native protein. When a protein in its native form, is subjected to a physical change like change in temperature or a chemical change like change in pH, denaturation of protein takes place. Explain the cause.

Hydrogen bonds and other intermolecular interactions connect the amino acid residues in proteins. The hydrogen bonds are disrupted when a physical or chemical change occurs, and the native protein...

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Match the compounds given in Column I with the oxidation state of cobalt present in it (given in Column II) and assign the correct code. with the oxidation state of cobalt present in it (given in Column II) and assign the correct code.

  Solution: \[\left( c \right)\text{ }\left( A\text{ }\to \text{ }5 \right),\text{ }\left( B\text{ }\to \text{ }1 \right),\text{ }\left( C\text{ }\to \text{ }4 \right),\text{ }\left( D\text{...

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Match the coordination compounds given in Column I with the central metal atoms given in Column II and assign the correct code : Code : (i) A (5) B (4) C (1) D (2) (ii) A (3) B (4) C (5) D (1) (iii) A (4) B (3) C (2) D (1) (iv) A (3) B (4) C (1) D (2)

Solution: \[\left( b \right)\text{ }\left( A\text{ }\to 5 \right),\text{ }\left( B\text{ }\to \text{ }4 \right),\text{ }\left( C\text{ }\to \text{ }1 \right),\text{ }\left( D~\to 2 \right)\]  ...

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(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement.Assertion: Network polymers are thermosetting. Reason: Network polymers have high molecular mass.

Option (i) is correct During polymerisation, extensive cross linking results in the creation of a three-dimensional network that is rigid, insoluble, and infusible.

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(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement. Assertion: For making rubber synthetically, isoprene molecules are polymerised. Reason: Neoprene (a polymer of chloroprene) is a synthetic rubber.

Option (v) is correct Natural rubber is made up of isoprene molecules, while neoprene, a synthetic rubber, is made up of chloroprene polymers.

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(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement.Assertion: Polyamides are best used as fibres because of high tensile strength. Reason: Strong intermolecular forces (like hydrogen bonding within polyamides) lead to close packing of chains and increase the crystalline character, hence, provide high tensile strength to polymers.

Option (ii) is correct Polyamides, such as nylon, are the most often used fibres. Because of the strong intermolecular hydrogen connection, they have a high tensile strength.

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(i) Assertion and reason both are correct statements but reason does not explain the assertion. (ii) Assertion and reason both are correct statements and reason explain the assertion. (iii) Both assertion and reason are the wrong statements. (iv) The assertion is correct statement and reason is the wrong statement. (v) The assertion is the wrong statement and reason is the correct statement.Assertion: Most of the Synthetic polymers are not biodegradable. Reason: Polymerisation process induces toxic character in organic molecules.

Option (iv) is correct Enzymatic hydrolysis and environmental oxidation do not destroy the majority of synthetic polymers. Toxic characteristics are not produced via polymerization.

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An aqueous pink solution of cobalt(II) chloride changes to deep blue on the addition of an excess of HCl. This is because____________. (a) [Co(H2O)6]2+ is transformed into [CoCl6]4– (b) [Co(H2O)6]2+ is transformed into [CoCl4]2– (c) tetrahedral complexes have smaller crystal field splitting than octahedral complexes. (d) tetrahedral complexes have larger crystal field splitting than octahedral complex.

Solution: (b, c) Aqueous pink arrangement of cobalt (II) chloride is because of electronic progress of electron from t2g to eg energy level of [Co(H2O)6]2+ complex. At the point when overabundance...

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Which of the following are characteristics of thermosetting polymers? (i) Heavily branched cross-linked polymers. (ii) Linear slightly branched long-chain molecules. (iii) Become infusible on moulding so cannot be reused. (iv) Soften on heating and harden on cooling, can be reused.

Option (i) and (iii) are the answers. Thermosetting polymers have a lot of branching cross links. They can't be used again since they don't melt when heated and can't be remoulded.

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Due to the presence of ambidentate ligands coordination compounds show isomerism. Palladium complexes of the type [Pd(C6H5)2(SCN)2] and [Pd(C6H5)2(NCS)2] are (a) linkage isomers (b) coordination isomers (c) ionisation isomers (d) geometrical isomers

Solution: (a) The ligands having two distinctive holding locales are known as ambident ligands e.g., NCS, NO2, and so forth Here, NCS has two restricting locales at N and S. Subsequently, NCS...

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When 0.1 mol COCl3(NH3)5 is treated with excess of AgNO3, 0.2 mol of AgCl are obtained. The conductivity of solution will correspond to (a) 1:3 electrolyte (b) 1:2 electrolyte (c) 1:1 electrolyte (d) 3:1 electrolyte

Solution: (b) One mole of AgNO3 accelerates one mole of chloride particle. In the above response, when 0.1 mole COCl3(NH3)5 is treated with abundance of AgNO3, 0.2 mole of AgCl are obtained hence,...

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The colour of the coordination compounds depends on the crystal field splitting. What will be the correct order of absorption of wavelength of light in the visible region, for the complexes, [Co(NH3)6]3+, [Co(CN)6]3–, [Co(H2O)6]3+ (a) [Co(CN)6]3–> [Co(NH3)6]3+>[Co(H2O)6]3+ (b) [Co(NH3)6]3+> [Co(H2O)6]3+> [Co(CN)6]3– (c) [Co(H2O)6]3+> [Co(NH3)6]3+> [Co(CN)6]3– (d) [Co(CN)6]3–> [Co(NH3)6]3+> [Co(H2O)6]3+

Solution:  

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A coordination compound CrCl3.4H2O hastens silver chloride when treated with silver nitrate. The molar conductance of its answer relates to a sum of two particles. Compose the primary recipe of the compound and name it.

Solution: Assuming it structures silver chloride, there is without one chlorine iota outside the coordination circle. The primary recipe must be [Cr(H2O)4Cl2]Cl. The name of this complex is...

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An answer of KMnO4 on decrease yields either lackluster arrangement or an earthy colored encourage or a green arrangement relying upon the pH of the arrangement. What various phases of the decrease do these address and how are they completed?

Solution: In acidic medium, permanganate changes to manganous particle which is lackluster.   \[MnO4-+8H+\text{ }+\text{ }5e-\to \text{ }Mn2+\text{ }+\text{ }4H2O\] (drab)   In basic...

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At the point when an orange arrangement containing Cr2O72–particle is treated with an antacid, a yellow arrangement is framed and when H+ particles are added to a yellow arrangement, an orange arrangement is acquired. Clarify for what reason does this occur?

Solution: At the point when Cr2O72–is treated with an antacid:   \[\left( orange \right)\text{ }Cr2O72+\text{ }OH-\to \text{ }2CrO42-\left( yellow \right)\] At the point when the yellow...

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At the point when an earthy colored compound of manganese (A) is treated with HCl it gives a gas (B). The gas taken in abundance responds with NH3 to give an unstable compound (C). Distinguish intensifies A, B and C.

Solution: At the point when earthy colored co pound of manganese (A) is treated with HCl it gives chlorine gas.   \[MnO2\text{ }+\text{ }4HCl\text{ }\to \text{ }MnCl2\text{ }+\text{ }Cl2\text{...

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In spite of the fact that +3 is the trademark oxidation state for lanthanoids however cerium additionally shows +4 oxidation state in light of the fact that (a) it has variable ionization enthalpy (b) it tends to accomplish respectable gas design (c) it tends to accomplish f° arrangement (d) it looks like Pb4+

Solution: (b, c) Cerium shows +4 oxidation state likewise on the grounds that it tends to accomplish respectable gas setup and achieve f° design. Ce – 4f15d'6s2 (Ce4+–4f°)

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As dichromate, Cr (VI) is a solid oxidizing specialist in acidic medium however, Mo (VI) in MoO3 and W (VI) in WO3 are not on the grounds that (a) Cr (VI) is more steady than Mo(VI) and W(VI) (b) Mo(VI) and W(VI) are more steady than Cr(VI) (c) higher oxidation conditions of heavier individuals from bunch 6 of change series are more steady (d) lower oxidation conditions of heavier individuals from bunch 6 of change series are more steady

Solution: (b, c) In d-block components, for heavier components, the higher oxidation states are more steady. Thus, Mo(VI) and W(VI) are more steady than Cr (VI). That is the reason, Cr (VI) as...

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For what reason is HCl not used to make the medium acidic in oxidation responses of KMnO4 in acidic medium? (a) Both HCl and KMn04 go about as oxidizing specialists. (b) KMnO4 oxidizes HCl into Cl2 which is likewise an oxidizing specialist. (c) KMnO4 is a more fragile oxidizing specialist than HCl. (d) KMnO4 goes about as a decreasing specialist within the sight of HCl.

Solution: (b) HCl isn't utilized to make the medium acidic in oxidation responses of KMnO4 in acidic medium. The explanation is that in case HCl is utilized, the oxygen delivered from KMnO4 + HCl is...

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In spite of the fact that zirconium has a place with 4d change series and hafnium to 5d change series and still, after all that they show comparative physical and substance properties in light of the fact that (a) both have a place with d-block (b) both have same number of electrons (c) both have comparative nuclear span (d) both have a place with a similar gathering of the intermittent table

Solution: (c) Zirconium and hafnium have comparable nuclear range thus they show comparable physical and synthetic properties.

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Most elevated oxidation condition of manganese in fluoride is +4 (MnF4) however most noteworthy oxidation state in oxides is +7 (Mn2O7) in light of the fact that (a) fluorine is more electronegative than oxygen (b) fluorine doesn’t have d-orbitals (c) fluorine settles lower oxidation state (d) in covalent mixtures fluorine can frame single bond just while oxygen shapes twofold bond

Solution: (d) The most noteworthy oxidation condition of manganese in fluoride is +4 (MnF4) yet in oxides it is +7 (Mn2O7) in light of the fact that in covalent mixtures fluorine can frame single...

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Which of the accompanying assertion isn’t right? (a) Copper frees hydrogen from acids (b) In its higher oxidation states, manganese structures stable mixtures with oxygen and fluorine (c) Mn3+ and Co3+ are oxidizing specialists in watery arrangement (d) Ti2+ and Cr2+ are decreasing specialists in watery arrangement

Solution: (a) Copper doesn't free hydrogen from acids. \[\begin{array}{*{35}{l}} Cu\text{ }+\text{ }2H2S04\text{ }\text{ }>\text{ }CuSO4\text{ }+\text{ }S02\text{ }+\text{ }2H2O  \\ ~  \\...

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Interstitial mixtures are shaped when little particles are caught inside the gem cross section of metals. Which of coming up next isn’t the trademark property of interstitial mixtures? (a) They have high liquefying focuses in contrast with unadulterated metals (b) They are exceptionally hard (c) They hold metallic conductivity (d) They are synthetically extremely receptive.

Solution: (d) Interstitial mixtures are synthetically idle.

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At the point when KMnO4 arrangement is added to oxalic corrosive arrangement, the decolourisation is delayed to start with yet becomes momentary after some time on the grounds that (a) CO2 is shaped as the item (b) Reaction is exothermic (c) Mn04 catalyzes the response (d) Mn2+ goes about as autocatalyst

Solution: (d) When KMnO4 arrangement is added to oxalic corrosive arrangement, the decolourisation is delayed first and foremost yet becomes immediate after some time in light of the fact that Mn2+...

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Aryl chlorides and bromides can be easily prepared by electrophilic substitution of arenes with chlorine and bromine respectively in the presence of Lewis acid catalysts. But why does the preparation of aryl iodides requires the presence of an oxidising agent?

Arenes' iodination can be reversed due to the production of HI. An oxidising agent, such as HNO3 or HIO4, oxidises HI to speed up the process and stabilise the result.

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Ethylene chloride and ethylidene chloride are isomers. Identify the correct statements. (i) Both the compounds form the same product on treatment with alcoholic KOH. (ii) Both the compounds form the same product on treatment with aq.NaOH. (iii) Both the compounds form the same product on reduction. (iv) Both the compounds are optically active.

Option (i) and (iii) are the answers. They give ethyne on treatment with alcoholic $\mathrm{KOH}$. $ \mathrm{CH}_{3} \mathrm{CHCl}_{2} \underset{\mathrm{KOH}}{\stackrel{\text { alc....

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Which of the following statements are correct about the mechanism of this reaction? (i) A carbocation will be formed as an intermediate in the reaction. (ii) OH–will attach the substrate (b) from one side and Cl- will leave it simultaneously from the other side. (iii) An unstable intermediate will be formed in which OH– and Cl– will be attached by weak bonds. (iv) The reaction proceeds through an SN1 mechanism.

Option (i) and (iv) are the answers. Because it is a tertiary halide, it undergoes the SN1 process, resulting in the formation of a carbocation as an intermediate.  

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Which of the following statements are correct about the reaction intermediate? (i) Intermediate (c) is unstable because in this carbon is attached to 5 atoms. (ii) Intermediate (c) is unstable because carbon atom is sp2 hybridised. (iii) Intermediate (c) is stable because carbon atom is sp2 hybridised. (iv) Intermediate (c) is less stable than the reactant (b).

Option (i) and (iv) are the answers. Intermediate (iii) is unstable in the above reaction because the carbon atom is linked to 5 atoms and is less stable than reactant (ii).

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Which of the following statements are correct about this reaction? (i) The given reaction follows the SN2 mechanism. (ii) (b) and (d) have the opposite configuration. (iii) (b) and (d) have the same configuration. (iv) The given reaction follows the SN1 mechanism.

Option (i) and (ii) are the answers. Alkyl halide is the main reactant in the given reaction. A transient condition is found here, in which one bond is broken and another is created synchronously,...

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Which of the statements are correct about the above reaction? (i) (a) and (e) both are nucleophiles. (ii) In (c) carbon atom is sp3 hybridised. (iii) In (c) carbon atom is sp2 hybridised. (iv) (a) and (e) both are electrophiles.

Option (i) and (iii) are the answers. Nucleophiles are HO and CF. The C atom is sp2 hybridised in (iii) due to the simultaneous creation of the C – OH bond and the breakdown of the C – Cl link. As a...

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Which is the correct increasing order of boiling points of the following compounds? 1-Bromoethane, 1-Bromopropane, 1-Bromobutane, Bromobenzene (i) Bromobenzene < 1-Bromobutane < 1-Bromopropane < 1-Bromoethane (ii) Bromobenzene < 1-Bromoethane < 1-Bromopropane < 1-Bromobutane (iii) 1-Bromopropane < 1-Bromobutane < 1-Bromoethane < Bromobenzene (iv) 1-Bromoethane < 1-Bromopropane < 1-Bromobutane < Bromobenzene

Option (iv) is the answer Reason: As the molecular mass of the alkyl halide grows, the boiling point rises.

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Which is the correct increasing order of boiling points of the following compounds? 1-Iodobutane, 1-Bromobutane, 1-Chlorobutane, Butane (i) Butane < 1-Chlorobutane < 1-Bromobutane < 1-Iodobutane (ii) 1-Iodobutane < 1-Bromobutane < 1-Chlorobutane < Butane (iii) Butane < 1-Iodobutane < 1-Bromobutane < 1-Chlorobutane (iv) Butane < 1-Chlorobutane < 1-Iodobutane < 1-BromobutaneSolution:

Option (i) is the answer. Explanation: The larger the surface area, the stronger the intermolecular forces of attraction and, as a result, the higher the boiling point. For comparable types of alkyl...

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Toluene reacts with a halogen in the presence of iron (III) chloride giving ortho and para halo compounds. The reaction is (i) Electrophilic elimination reaction (ii) Electrophilic substitution reaction (iii) Free radical addition reaction (iv) Nucleophilic substitution reaction

Option (ii) is the answer. In the presence of Iron(III) chloride, toluene interacts with halogen to produce ortho and para halo compounds in an electrophilic substitution process. The Cl atom...

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Which of the following reagents can be used to oxidise primary alcohols to aldehydes? (i) CrO3 in an anhydrous medium. (ii) KMnO4 in acidic medium. (iii) Pyridinium chlorochromate. (iv) Heat in the presence of Cu at 573K

Option (i), (iii) and (iv) are the answers. Primary alcohols can be oxidised to aldehydes using CrO3 in an anhydrous media. CrO3 serves as an oxidizer in this situation. As a result, option I is the...

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