Chemistry

Give examples and suggest reasons for the following features of the transition metal chemistry:
(i) The lowest oxide of transition metal is basic, the highest is amphoteric/acidic.
(ii) A transition metal exhibits highest oxidation state in oxides and fluorides.

(i) In the case of a lower oxide of a transition metal, the metal atom has a low oxidation state. This means that some of the valence electrons of the metal atom are not involved in bonding. As a...

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Primary alkyl halide C4H9Br (a) reacted with alcoholic KOH to give compound (b). Compound (b) is reacted with HBr to give (c) which is an isomer of (a). When (a) is reacted with sodium metal it gives compound (d), C8H18 which is different from the compound formed when n-butyl bromide is reacted with sodium. Give the structural formula of (a) and write the equations for all the reactions.

The formula C4H9Br is used to make two main alkyl halides. They're n-butyl bromide and isobutyl bromide, respectively. Compound (a) is therefore either nbutyl bromide or isobutyl bromide. Compound...

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Arrange the compounds of each set in order of reactivity towards SN2 displacement: (i) 2-Bromo-2-methylbutane, 1-Bromopentane, 2-Bromopentane (ii) 1-Bromo-3-methylbutane, 2-Bromo-2-methylbutane, 3-Bromo-2- methylbutane (iii) 1-Bromobutane, 1-Bromo-2,2-dimethylpropane, 1-Bromo-2-methylbutane, 1Bromo-3- methylbutane.

(i) The nucleophile approaches the carbon atom to which the leaving group is linked in an SN2 reaction. The reactivity for SN2 displacement reduces when the nucleophile is sterically inhibited. The...

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Predict all the alkenes that would be formed by dehydrohalogenation of the following halides with sodium ethoxide in ethanol and identify the major alkene: (i) 1-Bromo-1-methylcyclohexane (ii) 2-Chloro-2-methyl butane (iii) 2,2,3-Trimethyl-3-bromopentane.

(i) 1−bromo−1−methylcyclohexane In the given molecule, all β-hydrogens are equivalent. As a result, only one alkene is produced when the given molecule is dehydrogenated. (ii) Different sets of...

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For M2+/M and M3+/M2+ systems the EV values for some metals are as follows:
Cr2+/Cr = -0.9V       Cr3/Cr2+ = -0.4 V
Mn2+/Mn = -1.2V    Mn3+/Mn2+ = +1.5 V Fe2+/Fe = -0.4V Fe3+/Fe2+ = +0.8 V Use this data to comment upon: (i) the stability of Fe3+ in acid solution as compared to that of Cr3+ or Mn3+ and (ii) the ease with which iron can be oxidised as compared to a similar process for either chromium or manganese metal.

(i) The reduction potentials for the given pairs increase in the given order: Mn2+ / Mn < Cr2+ / Cr < Fe2+ /Fe So, the oxidation of Fe to Fe2+ is not as easy as the...

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