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.
Suggest the most important type of intermolecular attractive interaction in the following pairs.
(i) n-hexane and n-octane
(ii) I2 and CCl4
(iii) NaClO4 and water
(iv) methanol and acetone
(v) acetonitrile (CH3CN) and acetone (C3H6O).
Calculate the mass percentage of benzene (C6H6) and carbon tetrachloride (CCl4) if 22 g of benzene is dissolved in 122 g of carbon tetrachloride.
Henry's law constant for the molality of methane in benzene at 298 Kis 4.27 x 105 mm Hg. Calculate the solubility of methane in benzene at 298 Kunder 760 mm Hg.
Out of C and CO, which is a better reducing agent for ZnO ?
Which one of the following has the highest dipole moment?
(i) CH2Cl2
(ii) CHCl3
(iii) CCl4
Predict the major product of acid catalysed dehydration of
(i) 1-Methylcyclohexanol and
(ii) Butan-1-ol
Use Hund's rule to derive the electronic configuration of Ce3+ ion and calculate its magnetic moment on the basis of 'spin-only' formula.
In the series Sc (Z = 21) to Zn (Z = 30), the enthalpy of atomization of zinc is the lowest, i.e., 126 kJ mol−1. Why?
What is the coordination entity formed when excess of aqueous KCN is added to an aqueous solution of copper sulphate? Why is it that no precipitate of copper sulphide is obtained when H2S(g) is passed through this solution?
Classify the following solids in different categories based on the nature of intermolecular forces operating in them:
Potassium sulphate, tin, benzene, urea, ammonia, water, zinc sulphide, graphite, rubidium, argon, silicon carbide.
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