The proposed mechanism for hydration of ethene to yield ethanol is as follows:

The wrong step in the above mechanism is:

Which of the following reagents can be used to oxidize primary alcohols to aldehydes?

I.  ${\mathrm{CrO}}_3$ in anhydrous medium

II.  ${\mathrm{KMnO}}_4$ in acidic medium

III.  Pyridinium chlorochromate

IV.  Heat in the presence of Cu at 573K

Choose the correct option:
1. (I, II, III)
2. (II, III, IV)
3. (I, III, IV)
4. (I, II, IV)

Which option shows the correct increasing order of reactivity of the following compounds with HBr/HCl?
  

1.  I < II < III 

2.  II <I < III

3.  II < III < I 

4.  III < II < I 

The increasing order of reactivity of the following compounds towards acid-catalyzed dehydration is:

a.		b.
c.		d.

   \(\text{1-Methylcyclohexanol}~ \mathrm{\xrightarrow[]{acid \ catalysed \ dehydration}} ~\text A\) 

1. 2-Methylcyclohexene
2. 1-Methylcyclohexanol
3. 1-Methylcyclohexane
4. 1-Methylcyclohexene