IGCSE/GCSE/O & A Level/IB/University Student Forum

Qualification => Subject Doubts => GCE AS & A2 Level => Sciences => Topic started by: moon on June 06, 2010, 02:36:26 pm

Title: Chemistry ppr 4 Help!!!!
Post by: moon on June 06, 2010, 02:36:26 pm

this question from chemistry ppr4 June. 2005 Q.(1)

plz can anybody help me to draw the ameter in this circuit?

thanx in advance.

Title: Re: Chemistry ppr 4 Help!!!!
Post by: AndrewCedric on June 06, 2010, 03:52:30 pm

Just draw the ammeter in series with the positive end of the power supply and 1 of the electrodes.

Title: Re: Chemistry ppr 4 Help!!!!
Post by: insane.kid on June 06, 2010, 05:39:04 pm

Guys I have one question frm A level chem PAPER 4 S06 4d)iv) why do the Bromine have to be at 2,6 to OH y not 2,6 TO alkyl chain attached? hopefully you guys understood and plz reply soon :) thank you

Title: Re: Chemistry ppr 4 Help!!!!
Post by: CHEMMASTER6000 on June 06, 2010, 05:46:23 pm

we dont know why but , we learn it as a rule. OH is considered activating group which makes it combine to br as such .  cl are deactivating groups which makes it combine to 2 and 5 .

Title: Re: Chemistry ppr 4 Help!!!!
Post by: insane.kid on June 06, 2010, 05:51:46 pm

but y doesnt it go 2,6 to alkyl group y the OH and are u sure tht cl goes 2,5 :S i never knew tht

Title: Re: Chemistry ppr 4 Help!!!!
Post by: moon on June 06, 2010, 06:23:41 pm

can u plz check this answer?

Title: Re: Chemistry ppr 4 Help!!!!
Post by: CHEMMASTER6000 on June 07, 2010, 03:12:21 am

dude i looked at the paper, its an amino acid , nothing hppens to the amino acid. the only active groupas are the amide and the carboxylic acid on the sides and of course the r group. The R group is the benzene ring which is the reactive point  ;D