Physics, Chemistry and Biology: Post your doubts here!

[Xeeshan Rahat]

Even im takin the xtended course... u will be allowed to take a calculator... some geometrical instruments, a pencil ( the HB kind) and a blue pen ... bt no correctors are allowed...

Yes, I know these will be allowed but are there any other like periodic table then a formula sheet as well xD. Things like that? .xD.

Thanks In Advance,
Xeeshan Rahat.

 

[Xeeshan Rahat]

Nope! There are many I think...but for our syllabus I believe we only need to know 3 and they are:

1. Light Intensity
2. Temperature
3. Carbondioxide Concentration

Well in the syllabus it says Understand the concept of limiting factors...

It works like this: when one factor is limiting...as that factor increases the rate of photosynthesis increases up to a certain point and then another factor becomes the limiting factor...!

No, there are only 2 limiting factors in our IGCSE syllabus (bear in mind of CIE only) !

Which really are:
1. Light Intensity
&
2. Temperature

Thanks In Advance,
Xeeshan Rahat.

 

[ChemWhiz xoxo]

Nope... bt if u want... u can check the front page of every paper.. its mentioned there..

 

[Xeeshan Rahat]

Nope... bt if u want... u can check the front page of every paper.. its mentioned there..

Thanks Man, That Is Really The Answer I Want, Thanks ! xD.

 

[ChemWhiz xoxo]

Dude.. im a woman... cant see the 'xoxo'?? xD

 

[Xeeshan Rahat]

Dude.. im a woman... cant see the 'xoxo'?? xD

Haha Oh, Sorry ! Thanks WOMAN!

 

[ChemWhiz xoxo]

hmm. better... thou im a teen...

 

[AAnsarii]

When do r results come out?
plz pray i get all A*

 

[Xeeshan Rahat]

When do r results come out?
plz pray i get all A*

23 August, 2012 xD.

 

[Reema]

Does anyone here is takin der exams on oct/nov ?

 

[Xeeshan Rahat]

Does anyone here is takin der exams on oct/nov ?

I Am xD.

 

[Reema]

I Am xD.

r u a science student

 

[Xeeshan Rahat]

r u a science student

I am not sure what you mean, I think yes.

My subjects are:
1. English - As A First Language
2. Mathematics
3. Physics
4. Chemistry
5. Biology
6. ICT
7. Additional Mathematics

xD.

 

[joulie]

plz i need physics notes for 2013 syllabus

 

[joulie]

just

I am not sure what you mean, I think yes.

My subjects are:
1. English - As A First Language
2. Mathematics
3. Physics
4. Chemistry
5. Biology
6. ICT
7. Additional Mathematics

xD.

7 subjects ? in which country do u study

 

[NIM]

guys need help!!!
every help will be appreciated...
Q1_ Hydrated sodium carbonate has the formula Na2CO3.nH2O. An experiment was performed to determine n, the amount of water of crystallization. A sample of 50.00 g of hydrated sodium carbonate was dissolved in 250 cm3 of water. 20 cm3 of this solution reacted completely with 13.95 cm3 of 2.00 mol/dm3 hydrochloric acid.

Na2CO3(aq)+ 2HCl (aq) _______ 2NaCl(aq) +CO2(g)+H2O(l)
a)Calculate the amount of HCl acid reacted.
b). calculate the amount of sodium carbonate in the 20.00 cm3 of the solution used in the reaction.
c). calculate the concentration of sodium carbonate in the sample.
d). Calculate the molar mass of the hydrated sodium carbonate.
e). Calculate the value of n.

 

[Haider Nisar]

guyz i just wanted to ask that getting an A* is easy in bio,chem and physics!????

 

[Iridescent]

guyz i just wanted to ask that getting an A* is easy in bio,chem and physics!????

always depends on your hard work and a bit of intelligence too....for some its a piece of cake but some can't just reach upto there

 

[Haider Nisar]

dude but does these subjects have high A* range for example for physics the total marks are 200 and A* range would be how much??

 

[Atika]

in crystallisation you heat the solution then cool it down quickly ,this makes the molecules of the salt bind some water molecules around them forming crystals
in evaporation ,u remove all the water , so the salt is like a powder .also if you heated a crystallised salt ,you'll remove the water of crystallisation and it turns to powder.
yes, both are ways of extracting substances from solutions ,but evaporation can be done when the substance don't dissolve in the solution ,but for crystallisation to occur the substance has to dissolve in the solvent

Actually in crystallization we cool the solution to get the crystals but in evaporation, we heat it to separate the liquid. Like an example: in making of silicon chips we use crystallization method cuz if we would use evaporation it would damage it!!1