Draw Newman projection of the less stable staggered from of butane. b. Give reason for the relatively less stability of the staggered form.

(a) Draw sawhorse projection formulae for the two eclipsed conformations of butane. (b) What is the dihedral angle between adjaccent methyl groups? (c) Which conformer has greater torsional strain?

(a) Write the reaction of RCOOH with conc.H_2 OS_4 forming two possible cations. (b) Give the relative stabilities of the cations. ( c) Which cation undergoes (C-O) bond cleavage more readily ? (d) Calculate the van't Hoff factor, i (number of moles of particles formed per mole of solute), in both cases.

(a) Draw a sectional view of human female reproductive system and label the part where (i) eggs develop (ii) fertilsation take place. (iii) fertilised egg gets implanted. (b) Describe, in brief, the changes the uterus undergoes (i) to receive the zygote. (ii) if zygote is not formed.

Stereoisomers, which can be interconverted simply by rotation about sigma bonds, are confomational isomers while those, which can be converted only by breaking and remaking of bonds and not simply by rotation, are called configurational isomers. The angle between C-C and C-H bonds on adjacent carbon atoms in any conformation is called dihedral angle. The cyclic compounds most commonly found in nature containing six membered rings can exist in a conflormation that is almost completely free of strain. the most stable conformation of cyclohexane is chair form. According to Bayer strain theory, the greater deviation from the normal tetrahedral angle, greater is the angle strain or torsional strain and hence lesser is the stability of the cycloalkane. The energy barrier between eclipsed and staggered forms is:

Stereoisomers, which can be interconverted simply by rotation about sigma bonds, are confomational isomers while those, which can be converted only by breaking and remaking of bonds and not simply by rotation, are called configurational isomers. The angle between C-C and C-H bonds on adjacent carbon atoms in any conformation is called dihedral angle. The cyclic compounds most commonly found in nature containing six membered rings can exist in a conflormation that is almost completely free of strain. the most stable conformation of cyclohexane is chair form. According to Bayer strain theory, the greater deviation from the normal tetrahedral angle, greater is the angle strain or torsional strain and hence lesser is the stability of the cycloalkane. Dihedral angle is staggered and eclipsed conformation are:

Stereoisomers, which can be interconverted simply by rotation about sigma bonds, are confomational isomers while those, which can be converted only by breaking and remaking of bonds and not simply by rotation, are called configurational isomers. The angle between C-C and C-H bonds on adjacent carbon atoms in any conformation is called dihedral angle. The cyclic compounds most commonly found in nature containing six membered rings can exist in a conflormation that is almost completely free of strain. the most stable conformation of cyclohexane is chair form. According to Bayer strain theory, the greater deviation from the normal tetrahedral angle, greater is the angle strain or torsional strain and hence lesser is the stability of the cycloalkane. Select the correct sequence of decreasing order of stability?