Sarahisme

if you notice what i said in my first post, i asked the question, and then stated what i thought was correct!! so its not like i didn't give it a go ! but i agree with what you have said,, and i will try to be more self-sufficient in future Thanks Tom

i thought the whole point of this board was to get help when you don't understand something....even if it is something that other people may find 'basic'

so (a,b) is not including endpoints but [a,b] does?

so open intervals contain enpoints, whereas closed intervals do not contain endpoints?

what is the difference between an open interval (i.e. (a,b) ) and a closed interval (i.e. [a,b] )?? does the open interval not contain the endpoints (i.e. a & b) or something like that? :S Cheers Sarah

lol actually nevermind, i figured it out, sorry about that guys and gals

and if not i am not quite sure how to do the riemann sums of f(x) = 1 - .5x, [0,1] using Li=x(i) and Ui = x(i-1) note stuff in brackets is meant to be subscipt

hey is this right? i thought only the sum of just i = n(n+1)/2 ??

hmmm ok, yeah thats makes sense, thanks once again

allright, thanks for that

ok thanks

ok thanks everyone

yeah its the lone pairs bit, i don't see how there can be no lone pairs (or lone electrons even, that are not in pair (i.e.. just one electron)) ????

k, thanks BenSon

the answer given is (d) but yeah i've got no idea how to do it really :S

hey could i have some help on how to do this question? Thanks Sarah

oh and whats with the "3-0-3=0"??

right ok, cool so would you be able to quickly explain (if you have time) how the first one works (in the initial post of this thread)??

also just a second quick question.... shouldnt the N on the right side of the arrow have a postive charge (+) on it?

hmmm then i don't see how this mechnism reaction works.... does that OH coming in take that hydrogen away?

hey another questions guys.... isnt there one too many Hydrogens on the left most carbon atom (to the right of the arrow)??

yeah ok, its just i thought if it did have only 3 bonds, then it would have at least one free electron... ??

yeah thats what the answer booklet said, and i can see the correct results for 2,3 and 4 carbons but for carbon 1, shouldnt there be 4 bonds to it?

i don't agree with any of these answers: (but i am sure that i am wrong of course ).... so little help please if anyone has time