What are the common types of secondary structure of proteins?
There are two common types of secondary structure of proteins:
(i) ∝-helix structure
(ii) β-pleated sheet structure
∝- Helix structure:
In this structure, the -NH group of an amino acid residue forms H-bond with the group of the adjacent turn of the right-handed screw (∝-helix).
β-pleated sheet structure:
This structure is called so because it looks like the pleated folds of drapery. In this structure, all the peptide chains are stretched out to nearly the maximum extension and then laid side by side. These peptide chains are held together by intermolecular hydrogen bonds.
What happens when D-glucose is treated with the following reagents? (i)HI (ii)Bromine water (iii)HNO3
How do you explain the absence of aldehyde group in the pentaacetate of D-glucose?
Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
The melting points and solubility in water of amino acids are generally higher than that of the corresponding halo acids. Explain.
Define the following as related to proteins
(i) Peptide linkage (ii) Primary structure (iii) Denaturation.
What products would be formed when a nucleotide from DNA containing thymine is hydrolysed?
The two strands in DNA are not identical but are complementary. Explain.
Enumerate the reactions of D-glucose which cannot be explained by its open chain structure.
What are nucleic acids? Mention their two important functions.
Where does the water present in the egg go after boiling the egg?
For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.
Write the formulas for the following coordination compounds:
(i) Tetraamminediaquacobalt (III) chloride
(ii) Potassium tetracyanonickelate(II)
(iii) Tris(ethane-1,2-diamine) chromium(III) chloride
(iv) Amminebromidochloridonitrito-N-platinate(II)
(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate
(vi) Iron(III) hexacyanoferrate(II)
(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N
(ii) Write IUPAC names of all the isomers.
(iii) What type of isomerism is exhibited by different pairs of amines?
Why are solids rigid?
Write any two characteristics of Chemisorption.
Write the structures of the following compounds.
(i) α-Methoxypropionaldehyde
(ii) 3-Hydroxybutanal
(iii) 2-Hydroxycyclopentane carbaldehyde
(iv) 4-Oxopentanal
(v) Di-sec-butyl ketone
(vi) 4-Fluoroacetophenone
Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?
Why are pentahalides more covalent than trihalides?
Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?
Write structures of the following compounds:
(i) 2-Chloro-3-methylpentane
(ii) 1-Chloro-4-ethylcyclohexane
(iii) 4-tert. Butyl-3-iodoheptane
(iv) 1,4-Dibromobut-2-ene
(v) 1-Bromo-4-sec. butyl-2-methylbenzene
What is meant by 'disproportionation'? Give two examples of disproportionation reaction in aqueous solution.
Give the uses of freon 12, DDT, carbon tetrachloride and iodoform.
How is leaching carried out in case of low grade copper ores?
Explain why Cu+ ion is not stable in aqueous solutions?
Explain why propanol has higher boiling point than that of the hydrocarbon, butane?
Is it true that under certain conditions, Mg can reduce SiO2 and Si can reduce MgO? What are those conditions?
Define conductivity and molar conductivity for the solution of an electrolyte. Discuss their variation with concentration.
Calculate the potential of hydrogen electrode in contact with a solution whose pH is 10.
The experimental data for decomposition of N2O5
[2N2O5 → 4NO2 + O2]
in gas phase at 318K are given below:
t/s | 0 | 400 | 800 | 1200 | 1600 | 2000 | 2400 | 2800 | 3200 |
102 × [N2O5] mol L-1 | 1.63 | 1.36 | 1.14 | 0.93 | 0.78 | 0.64 | 0.53 | 0.43 | 0.35 |
(i) Plot [N2O5] against t.
(ii) Find the half-life period for the reaction.
(iii) Draw a graph between log[N2O5] and t.
(iv) What is the rate law ?
(v) Calculate the rate constant.
(vi) Calculate the half-life period from k and compare it with (ii).
How the following conversions can be carried out?
(i) Propene to propan-1-ol
(ii) Ethanol to but-1-yne
(iii) 1-Bromopropane to 2-bromopropane
(iv) Toluene to benzyl alcohol
(v) Benzene to 4-bromonitrobenzene
(vi) Benzyl alcohol to 2-phenylethanoic acid
(vii) Ethanol to propanenitrile
(viii) Aniline to chlorobenzene
(ix) 2-Chlorobutane to 3, 4-dimethylhexane
(x) 2-Methyl-1-propene to 2-chloro-2-methylpropane
(xi) Ethyl chloride to propanoic acid
(xii) But-1-ene to n-butyliodide
(xiii) 2-Chloropropane to 1-propanol
(xiv) Isopropyl alcohol to iodoform
(xv) Chlorobenzene to p-nitrophenol
(xvi) 2-Bromopropane to 1-bromopropane
(xvii) Chloroethane to butane
(xviii) Benzene to diphenyl
(xix) tert-Butyl bromide to isobutyl bromide
(xx) Aniline to phenylisocyanide