Explain the difference between Buna-N and Buna-S.
Buna – N
Buna - N is a copolymer of 1,3−butadiene and acrylonitrile. It is also called Nitrile rubber (NBR). It is obtained by polymerization of 1,3-butadiene and acrylonitrile in the presence of sodium .It is used for making oil seels, manufacturing of tank linings, protective gloves etc.
Buna − S
Buna - S is a copolymer of 1,3−butadiene and styrene. It is obtained by polymerization of 1,3-Butadiene and styrene in the ratio 3:1 in the presence of sodium.
In Buna - S, Bu stands for butadiene, Na for sodium and S for styrene. It is also called SBR (Styrene Butadiene Rubber).It has slightly less tensile strength than natural rubber. It is used for making automobile tyres, rubber soles, belts, hoses etc.
Write the names and structures of the monomers of the following polymers:
(i) Buna-S (ii) Buna-N
(iii) Dacron (iv) Neoprene
What is a biodegradable polymer? Give an example of a biodegradable aliphatic polyester.
Arrange the following polymers in increasing order of their intermolecular forces.
(i) Nylon 6, 6, Buna-S, Polythene.
(ii) Nylon 6, Neoprene, Polyvinyl chloride.
How are polymers classified on the basis of structure?
Define thermoplastics and thermosetting polymers with two examples of each.
Explain the term copolymerisation and give two examples.
Write the monomers used for getting the following polymers. (i) Polyvinyl chloride (ii) Teflon (iii) Bakelite
How do you explain the functionality of a monomer?
Identify the monomer in the following polymeric structures.
(i)
(ii)
What are the monomeric repeating units of Nylon-6 and Nylon-6, 6?
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?
Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.
Write the reactions of (i) aromatic and (ii) aliphatic primary amines with nitrous acid.
What are monosaccharides?
An aromatic compound 'A' on treatment with aqueous ammonia and heating forms compound 'B' which on heating with Br2 and KOH forms a compound 'C' of molecular formula C6H7N. Write the structures and IUPAC names of compounds A, B and C.
Write the reactions of (i) aromatic and (ii) aliphatic primary amines with nitrous acid.
Discuss the general characteristics of Group 15 elements with reference to their electronic configuration, oxidation state, atomic size, ionisation enthalpy and electronegativity.
Write the reactions of F2 and Cl2 with water.
Convert
(i) 3-Methylaniline into 3-nitrotoluene.
(ii) Aniline into 1,3,5-tribromobenzene.
How will you convert:
(i) Ethanoic acid into methanamine
(ii) Hexanenitrile into 1-aminopentane
(iii) Methanol to ethanoic acid
(iv) Ethanamine into methanamine
(v) Ethanoic acid into propanoic acid
(vi) Methanamine into ethanamine
(vii) Nitromethane into dimethylamine
(viii) Propanoic acid into ethanoic acid
Write short notes on the following:
(i) Carbylamine reaction (ii) Diazotisation
(iii) Hofmann's bromamide reaction (iv) Coupling reaction
(v) Ammonolysis (vi) Acetylation
(vii) Gabriel phthalimide synthesis.
Accomplish the following conversions:
(i) Nitrobenzene to benzoic acid
(ii) Benzene to m-bromophenol
(iii) Benzoic acid to aniline
(iv) Aniline to 2,4,6-tribromofluorobenzene
(v) Benzyl chloride to 2-phenylethanamine
(vi) Chlorobenzene to p-chloroaniline
(vii) Aniline to p-bromoaniline
(viii) Benzamide to toluene
(ix) Aniline to benzyl alcohol.
Very good answer thnk u
which one is more swells in oil or solvant
Not appropriate answer....
In book sodium is not given, CN is given....
Wonderful answer
Wonderful â£ï¸ thank u for helping me ððð
Very good site and helpful one
Natural rubber hai ya synthetic rubber
Clearly expiation
Clearly explanation