Which of the following reactions of methane is incomplete combustion?
Dining incomplete combustion of alkanes with insufficient amount of air or dioxygen, carbon black is formed which is used in the manufacture of ink, printer ink, black pigments and as filters. Thus,
In the alkane, CH3CH2—C(CH3)2—CH2—CH(CH3)2, identify 1 °, 2 °, 3 ° carbon atoms and give the number of H-atoms bonded to each one of these.
Out of benzene, m-dinitrobenzene and toluene which will undergo nitration most easily and why?
Nucleophiles and electrophiles are reaction intermediates having electron rich and electron deficient centres respectively. Hence, they tend to attack electron deficient and electron rich centres respectively. Classify the following species as electrophiles and nucleophiles.
Which of the following are correct?
(a) CH3 – O – CH+2 is more stable than CH3 – CH+2
(b) (CH3)2CH+ is less stable than CH3 – CH2 – CH+2
(c) CH2 = CH – CH+2 is more stable than CH3 – CH2 – CH+2
(d) CH2 = CH+ is more stable than CH3 – CH+2
Arrange the following: HCl, HBr, HI, HF in order of decreasing reactivity towards alkenes.
Arrange the following set of compounds in order of their decreasing relative reactivity with an electrophile, E+.
(a) Chlorobenzene, 2, 4-dinitrochlorobenzene, p-nitrochlorobenzene
(b) Toluene,p—H3C—C6H4—NO2, p—O2N—C6H4—NO2.
Why does benzene undergo electrophilic substitution reactions easily and nucleophilic substitutions with difficulty?
For the following compounds, write structural formulas and IUPAC names for all possible isomers having the number of double or triple bond as indicated:
(a) C4H8 (one double bond) (b) C5H8 (one triple bond)
Write chemical equations for the combustion reaction of the following hydrocarbons, (i) Butane (ii) Pentene (iii) Hexyne (iv) Toluene
Write the IUPAC names of the following compounds.
(i) (CH3)CCH2C(CH3)3 (ii) (CH3)2C(C2H5)2
Discuss the preparation of alkanes by Wurtz reaction. What is the limitaHon of the reaction?
Arrange the following alkyl halides in decreasing order of the rate of β -elimination reaction with alcoholic KOH.
The relative reactivity of 1 °, 2 ° and 3 ° hydrogens towards chlorination is 1: 3.8 : 5. Calculate the percentages of all monochlorinated products obtained from 2-methylbutane.
(a) What effect the branching of an alkane has on its melting point?
(b) Which of the following has highest boiling point?
(i) 2-methyl pentane
(ii) 2, 3-diethyl butane
(iii) 2, 2-dimethyl butane
How will you demonstrate that double bonds of benzene are somewhat different from that of olefins?
The molecules having dipole moment are________ .
(a) 2,2-Dimethylpropane
(b) trans-Pent-2-ene
(c) cw-Hex-3-ene
(d) 2,2,3,3-Tetramethylbutane
(a) Why are alkenes called unsaturated hydrocarbons?
(b) How will you test the presence of double bond in an alkene?
(c) Name the products formed when propene is subjected to ozonolysis.
Which are the correct IUPAC names of the following compound
(a) 5-(2′,2′-Dimethylpropyl)decane
(b) 4-Butyl-2,2-dimethylnonane
(c) 2,2-Dimethyl-4-pentyloctane
(d) 5-neo-Pentyldecane
Alkynes on reduction with sodium in liquid ammonia form trans alkenes. Will butene formed on the reduction of but-2-yne show geometrical isomerism?
Explain the term aromaticity. What are the necessary conditions for any compound to show aromaticity?
Why do alkenes prefer to undergo electrophilic addition reaction while arenes prefer electrophilic substitution reaction? Explain.
Rotation around carbon-carbon single bond of ethane is not completely free. Justify the statement.
Arrange the following set of compounds in the order of their decreasing . relative reactivity with an electrophile. Give reason.
Why does the presence of a nitro group-make the benzene ring less reactive in comparison to the unsubstituted benzene ring? Explain.
An alkene ‘A’ contains three C—C, eight C—H, a-bonds, and one C—C n-bond. ‘A’ on ozonolysis gives two moles of an aldehyde of molar mass 44 u. Write the IUPAC name of’A’.
Draw the cis- and trans-structures for hex-2-ene. Which iosmer will have higher b.p. and why?
