Biology; Chemistry; Physics: Post your doubts here!

[nightmaressana]

Yes the last part of theory paper has changed... They have Section C now, where you have to do one of the two questions...

For Chemistry read this, If you still have problems you can post then...

if we increase the temp, pressure of add the catalyst or surface area, the reaction will only speed up. but if we increase the quantity and the concentration, the products would be doubled, right? for instance if in one reaction with H2SO4 we used 1 mole of magnesium and 1mol/dm3 H2SO4 but in the other, if we increased the concentration to 2mol/dm3, the products would be doubled, wouldnt they?

 

[CaptainDanger]

Yes... It will increase the amount of product produced...

 

[nightmaressana]

thanx!

 

[legion]

in phy ATP graphs, is it necessary to dram best fit in a line or u can draw curved graph as well?

 

[Iridescent]

Yes... It will increase the amount of product produced...

Bt wat bout da limiting agent? Mg here iz da limiting agent so won't da amount of products be da same bt da reaction wud take les tym to finish?

 

[Nibz]

in phy ATP graphs, is it necessary to dram best fit in a line or u can draw curved graph as well?

In Physics ATP, you should draw a line of best fit.
While in other papers, if not mentioned, you can draw a point to point graph (line graph).

 

[safwana rahaman]

Assalam-o-Allaikum and Hi everyone ,
hope u all are doin great !

Well as the topic says help for chemistry biology and Physics is available here that means that u can ask any mind blowing question or ask any question regarding a particular topic or ask abt any questions from Past paper or any of your text books. 8) :Yahoo!:

I made this topic so that people dont make many posts asking abt bio,physics or chemistry individually but they can post their reply here where it can be answered with ease and the members wont have to go searching for topics to help! !

So what are u waiting for now write ur questions here !
THANKS and Bye or Allah Hafiz ! :wink: :good:

Help me ,
describe the penicillum production briefly

 

[scouserlfc]

WA!
Penicillium production is carried out in the fermenters,which are big large cylindrical tanks which have a capacity of more then a 100000 litres.First the nutrients for the Penicillium is put in the fermenter,these include carbohydrates (can be in the form of glucose or lactose ),proteins in the form of corn steep,mineral salts and the temperature of the fermenter is adjusted to between 26 degrees Celsius,air is allowed to pass in the fermenter as the penicillium produces penicillin aerobically.Also the Ph of the solution is adjusted to between 5 and 6 .After this all the strain of penicillium is added to the fermenter and is allowed to multiply and grow,after a few days the growth stops and the production begins,the temperature for the production is adjusted accordingly.the process is non continuous as the penicillium always uses up t he nutrients for its use and therefrore at some point the condition in the fermenter will not be useful for it to produce anything so at this point of time or after a desired quatity of penicillin is produced the process is stopped the liquid in fermenter is removed filtered to remove penicillium and then distilled out for penicillinthis is known as batch production system ,the remaining solution is returned to the fermenter where it is used again by mixing new nutrients with it !
A computer is connected to this process and it keeps check of all the constituents in the solution and the conditions so that they can be adjusted !

Hope u get it !

 

[hassan100]

if we increase the temp, pressure of add the catalyst or surface area, the reaction will only speed up. but if we increase the quantity and the concentration, the products would be doubled, right? for instance if in one reaction with H2SO4 we used 1 mole of magnesium and 1mol/dm3 H2SO4 but in the other, if we increased the concentration to 2mol/dm3, the products would be doubled, wouldnt they?

no they wont .increase in concentration also increases teh speed of reaction while increasing in quantity would double the products

Hop[e u get it

 

[abcde]

if we increase the temp, pressure of add the catalyst or surface area, the reaction will only speed up. but if we increase the quantity and the concentration, the products would be doubled, right? for instance if in one reaction with H2SO4 we used 1 mole of magnesium and 1mol/dm3 H2SO4 but in the other, if we increased the concentration to 2mol/dm3, the products would be doubled, wouldnt they?

AoA!
Actually, the amount of products formed would remain the same since magnesium becomes the limiting reactant. Had magnesium been in excess, you would've obtained twice the original amount of products by doubling the concentration of H2SO4 (aq).

 

[Iridescent]

AoA!
Actually, the amount of products formed would remain the same since magnesium becomes the limiting reactant. Had magnesium been in excess, you would've obtained twice the original amount of products by doubling the concentration of H2SO4 (aq).

Xactly wat i was saying!

 

[Abdullah Yousuf]

I have some good notes for O-level Chem

 

[scouserlfc]

I have some good notes for O-level Chem

so what are u waiting for,i guess u have them on paper and cant get it on the computer !

 

[Abdullah Yousuf]

yes & no

 

[scouserlfc]

Ill check these out later thanks for posting !

 

[tdk]

I dont think u will get a question like this ! Its way too advanced too seperate two ionic and soluble salts with very less differences in them !

Thank u so much.

 

[KumaiL JavaiD]

how should i prepare for physics atp's paper as it don't have any pattern..confusedd

 

[abcde]

how should i prepare for physics atp's paper as it don't have any pattern..confusedd

See the Examiner Tips and practice maximum past papers.

 

[snowbrood]

how should i prepare for physics atp's paper as it don't have any pattern..confusedd

u dont have to be confused guy it is the easiest of all the papers theory paper is the hardest... just practise past papers and make sure that u learn graphical analysis of number of chapters such as kinematics waves electricity... electricity and waves come frequently so have a good command in these chapters wish yeah all the best

 

[snowbrood]

is the hydrogen bonding in our syllabus