Biology; Chemistry; Physics: Post your doubts here!

[ayeshaK]

hope this helps:
http://en.wikipedia.org/wiki/File:Nitrogen_Cycle.svg

Thankyou !! Also can u tell me wether teethscome in paper atp or paper 2

 

[multixamza01]

Thankyou !! Also can u tell me wether teethscome in paper atp or paper 2

i'd say Paper 2 and Paper 1 .
but do the whole book once . Anything can come from anything for anything . CIE can't be trusted .

 

[ayeshaK]

Its not in

i'd say Paper 2 and Paper 1 .
but do the whole book once . Anything can come from anything for anything . CIE can't be trusted .

Its not in the book i read it frim the net all the teeths and types !!

 

[multixamza01]

Its not in
Its not in the book i read it frim the net all the teeths and types !!

also search tooth decay! that is important topic

 

[ayeshaK]

also search tooth decay! that is important topic

Oh thanku i will !! Also have you done insects and mammals abd amphibians etc ?

 

[multixamza01]

Oh thanku i will !! Also have you done insects and mammals abd amphibians etc ?

No.
Classification is no longer ''In Of Syllabus''.
Cie kicked it ''Out Of Syllabus''

 

[ayeshaK]

Oh really dats good

No.
Classification is no longer ''In Of Syllabus''.
Cie kicked it ''Out Of Syllabus''

Oh really dats good

 

[ashiqbal]

No if we add charcoal there may be errors !! We wont even know if all the indicator is removed by the charcoal and even how much amount we need to use !! The best is to repeat the experimentbwhich also the examiner requires !!
http://www.xtremepapers.com/revision/gcse/chemistry/acids_bases_and_salts.php
Mentioned in this link !!

if you have read marking scheme, it is repeated various times that(allow adding charcoal to remove indicator!

 

[ayeshaK]

if you have read marking scheme, it is repeated various times that(allow adding charcoal to remove indicator!

Ohkay

 

[mohammadusman96]

any1 with chem ATP notes??

 

[Spunkyfarhan]

angle A will be 40 cuz B and C angle are 70. so apply sine rule.
7.6 (the line BC)/sin(40) = (x+3.8)/ sin(70)

x= 7.31 cm
correct me if its wrong

Thnz =D!

 

[ayeshaK]

Can anybody help me with the instruction of how to prepare a microscopic slide as i have seen it in many papers !! ? Thankyou

 

[beeloooo]

http://www.xtremepapers.com/papers/...al O Level/Chemistry (5070)/5070_w05_ms_2.pdf

 

[beeloooo]

i do not find this mark scheme as authentic !!! so plz help and check for q.4,5,6 answers is it correct esp. da volume of CO2 ??

 

[SalmanPakRocks]

i do not find this mark scheme as authentic !!! so plz help and check for q.4,5,6 answers is it correct esp. da volume of CO2 ??

Marking Scheme is always authentic, rarely it contains an error. I have solved the paper for following year and I found no difficulty. Can you please specify which question you want me to solve?

 

[Vogue]

1) what is the useful product wen yeast is used in bread making; is ethanol useful or CO2?
2)What is the function of SiO2(silica) in the equation: CaO+ SiO2= CaSiO3
a) basic oxide b) reducing agent c) acidic oxide d) oxidizing agent

 

[Vogue]

can we use digital indicator in titration instead of repeating the titration?

plz explain abt this digital indicator cz i never heard abt it in my chem class

 

[Spidey21]

1) what is the useful product wen yeast is used in bread making; is ethanol useful or CO2?
2)What is the function of SiO2(silica) in the equation: CaO+ SiO2= CaSiO3
a) basic oxide b) reducing agent c) acidic oxide d) oxidizing agent

1) CO2 is useful because ethanol does nothing....rarely anything...but CO2 , produced by yeast by respiration, gives rise to the Bread and makes it porous....this way CO2 is useful...ethanol is a waste product which evaporates during BAking..

A) a basic oxide is formed when oxygen reacts with metal....for example NaOH...
B) a reducing Agent is a reagent that oxidises itself to reduce another...for example KI..
C) Acidic Oxide is formed when oxygen reacts with a non metal....for example CO2...
D) Oxidising Agent oxidises the other reagent and reduces itself just like the reducing agent...

2) i am not sure so let me confirm for this part...

and if there is any mistake please do tell me!!

 

[Vogue]

1) CO2 is useful because ethanol does nothing....rarely anything...but CO2 , produced by yeast by respiration, gives rise to the Bread and makes it porous....this way CO2 is useful...ethanol is a waste product which evaporates during BAking..

A) a basic oxide is formed when oxygen reacts with metal....for example NaOH...
B) a reducing Agent is a reagent that oxidises itself to reduce another...for example KI..
C) Acidic Oxide is formed when oxygen reacts with a non metal....for example CO2...
D) Oxidising Agent oxidises the other reagent and reduces itself just like the reducing agent...

2) i am not sure so let me confirm for this part...

and if there is any mistake please do tell me!!

i guess u misunderstood the question. actually question 2 is a MCQ nd a,b,c,d r the options
i think u explained those four terms from a to d, isn't it?

 

[Spunkyfarhan]

i guess u misunderstood the question. actually question 2 is a MCQ nd a,b,c,d r the options
i think u explained those four terms from a to d, isn't it?

PLZZZZ CAN SOMEONE TELL MEH HOW TO DO PAPER 6 ? HELPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPPP!