Hello, I need to make sure I understand some of the reactions correctly... For example: CH2OHCH3 in H+ will give us CH2=CH2. I would think that here the H+ bonded with the OH resulting in H2O (a leaving group), but I am not sure what happens to the other leaving H. In RC≡CR' in Na/NH3, we get RCH=CHR' in an anti addition. Where did the 2 H come from? The NH3? RCH=CH2 in H3O+ gives RCHOHCH3. Did the OH and H come from the H3O+? Do we then have one last H that does not bond with the molecule? And did the OH add to the C bonded with the R because it is the most substituted carbon? In RCH=CH2 in (1) Hg(OAc)2/H2O and (2) NaBH4, NaOH, we get RCHOHCH3. Where did the OH and H come from? Did the OH add to the C bonded with the R because it is the most substituted carbon? In RCH=CH2 in (1) BH3/THF and (2) H2O2/OH- we get RCH2CH2OH. Did the OH add to the C because it was the least substituted? Also, is the mechanism the following: first, Br (from BH3) bonds with the least subst. carbon, and H also from BH3 adds to the other C, thus breaking the double bond. Then in step (2) Br is replaced by OH, from OH-. And finally: a) ROH + SOCl2 -> RCl and b) ROH + TsCl ---(base)--> ROTs These 2 reactions confuse me. I thought that in a) the H would bond with a Cl giving HCl + RSOCl. Why does it give RCl? However in b) what I thought would happen in a) does take place. H and Cl bond, resulting in ROTs. Why? Thank you so much for your help, I hope I was clear enough!