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

Qualification => Subject Doubts => GCE AS & A2 Level => Sciences => Topic started by: unknown 101 on May 24, 2010, 12:32:57 am

Title: WHAT THE HELL !!!!!!!!!!!!
Post by: unknown 101 on May 24, 2010, 12:32:57 am
for all the people taking biology AS (cie)
check question 25 in nov 03
and check question 27 in jun 08
they are the same question!!
so.....
am i imagining or do they have different answers in their mark schemes

????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????
Title: Re: WHAT THE HELL !!!!!!!!!!!!
Post by: thomas234 on May 24, 2010, 04:35:28 am
You do understand that there is a difference between solute concentration & solute potential, correct?
Title: Re: WHAT THE HELL !!!!!!!!!!!!
Post by: cashem'up on May 24, 2010, 07:13:39 am
for all the people taking biology AS (cie)
check question 25 in nov 03
and check question 27 in jun 08
they are the same question!!
so.....
am i imagining or do they have different answers in their mark schemes

????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????????

yea basically when we are considering solute conc the more the solute the greater conc.......
HOWEVER
its different for solute potential
u obviously noe distilled water has water potential of 0 and water potential is solute potential + pressure potential.........now here we have no pressure so water pot.= sol pot......which is 0......rite now as u can see the less the solute the higher the value of solute potential......so when we consider solute potential....... there is more solute so  solute potential will be more negative and the value is low

hope it helps  ;D ;D ;D
thx
Title: Re: WHAT THE HELL !!!!!!!!!!!!
Post by: unknown 101 on May 24, 2010, 12:46:53 pm
You do understand that there is a difference between solute concentration & solute potential, correct?

ohhh, my bad i must have misread the question !!! :P
Title: Re: WHAT THE HELL !!!!!!!!!!!!
Post by: unknown 101 on May 24, 2010, 12:47:29 pm
yea basically when we are considering solute conc the more the solute the greater conc.......
HOWEVER
its different for solute potential
u obviously noe distilled water has water potential of 0 and water potential is solute potential + pressure potential.........now here we have no pressure so water pot.= sol pot......which is 0......rite now as u can see the less the solute the higher the value of solute potential......so when we consider solute potential....... there is more solute so  solute potential will be more negative and the value is low

hope it helps  ;D ;D ;D
thx


yea thanks it did :)