[Joules23]

Where did the 2nd Hydrogen come from?? in the CH3Ch2CH2CH2--OH2
How did the OH become H2O


Also, can someone tell me how to order the relative magnitudes such as this below

[tamim83]

The proton came from the acid that was added.  When strong acid is added to an alcohol, you end up protonating the hydroxyl group on the alcohol forming "water", which is an excellent leaving group. 

For the second one, you need to look at the "hills" for each step.  For step one A is lower in energy than B so the activation energy is higher going from A to B.  So the rate constant for A to B should be smaller than the rate constant from B to A.  This translates to the rate of A to B also being smaller. Thus K-1 is larger than K1.  Next we have B to C, which has a larger activation energy (bigger hill compared to A to B).  So these rate constants and rates will be smaller than those for A to B.  You can use the same reasoning I outlined above for A to B to order K-2 and K2, except the situation is reversed, C has a higher energy than B. 

[Joules23]

OK Now i understand clearly, unfortunately my exam was this morning, before you posted   ...Thanks for the explanation though