Physics, Chemistry and Biology: Post your doubts here!

[Phoenix Blood]

And these two also

First screenshot,

a) insert UI paper in the drink,
notice color change,
compare the color change with colors on the ph chart to know its ph

b) chromatography, yeah.
mention the chromatography paper and the base line pencilled on it,
a suitable solvent in which the paper will be dipped,
then say something like the different pigments will travel at different rates across the chromatogram,
and hence will be separated and each would be seen indivisually across different places on the ppr

c) attach a calibrated gas syringe at the mouth of the gas can and read off the value of volume from it.

 

[Phoenix Blood]

And these two also

second screenshot,

a) not so sure-
so the gas cools considerably and doesn't cause a stir in the limewater, thus not affecting results.

b) maybe that the funnel above the burning candle allowed gases from the air to enter the system

c) its the drawing force that allows the gas to move further across the apparatus

 

[Phoenix Blood]

About physics,
Can anybody tell me whats included in paper 1,4 and 6?

paper one is simple multiple choiced questions. You have a question, then you're given four options to select your answer from. there are a set of 40 questions to answer.

like this -

paper six is an alternative paper to science practicals, asking to label apparatus and questions regarding basic experiments are tested upon.

 

[Ushnaaa]

paper one is simple multiple choiced questions. You have a question, then you're given four options to select your answer from. there are a set of 40 questions to answer.

like this -

paper six is an alternative paper to science practicals, asking to label apparatus and questions regarding basic experiments are tested upon.

Thanks for telling but my bad,I know that in paper 1 there are mcqs,paper 4 is theory and paper 6 is atp,I was getting confused in another thing but its cleared now,thanks again!

 

[shaz.ch]

A very simple question from me... What is the difference between evaporation and crystallisation... What does one method offer that the other does not? I'm posing this question because both methods of separation seem to satisfy the same objective: extracting a dissolved substance from a solution...

evaporation in simple words mean change or liquid into vapour while crystallisation means change of liquid into solid.

 

[sj0007]

Really confused about the potential divider? any help...............

 

[NOneed2speedd]

second screenshot,

a) not so sure-
so the gas cools considerably and doesn't cause a stir in the limewater, thus not affecting results.

b) maybe that the funnel above the burning candle allowed gases from the air to enter the system

c) its the drawing force that allows the gas to move further across the apparatus

Thanks for helping

 

[Phoenix Blood]

Thanks for helping

You're welcome c:

 

[sj0007]

Umm.........I wanted to ask wether the isomerism of alcohols is in the syllabus.......thnx

 

[Sara.H]

Guys could anyone help?! Especially (ii) I'm stuck wiz it

 

[omar adel hassan]

what happens when glucose level is low in the blood

 

[Atharva Joshi]

what happens when glucose level is low in the blood

The hormone glucagon is secreted, which converts glycogen into glucose. (Glycogen is stored in the liver)

 

[IGCSE MAN]

1. In a certain organism, two traits are determined by two pairs of alleles, each of which shows dominance. One trait is determined by some combination of the alleles A and a. The other trait is determined by some combination of the alleles B and b, which are located on a different chromosome from A and a. Construct a complete Punnett square to show the results of a cross between two parents with genotypes Aabb (parent #1) and AaBb (parent #2). Then determine each of the following:
   
   a) What fraction of the offspring is expected to have the same genotype as parent #1?
   b) What fraction of the offspring is expected to have the same phenotype as parent #2?
   c) What fraction of the offspring is expected to be dihybrid?
   
   Please help me, i have a test tmmw!!! if possible please mail me the answer at [email protected]

 

[IGCSE MAN]

In a certain organism, two traits are determined by two pairs of alleles, each of which shows dominance. One trait is determined by some combination of the alleles A and a. The other trait is determined by some combination of the alleles B and b, which are located on a different chromosome from A and a. Construct a complete Punnett square to show the results of a cross between two parents with genotypes Aabb (parent #1) and AaBb (parent #2). Then determine each of the following:

a) What fraction of the offspring is expected to have the same genotype as parent #1?
b) What fraction of the offspring is expected to have the same phenotype as parent #2?
c) What fraction of the offspring is expected to be dihybrid?

Please help me, i have a test tmmw!!! if possible please mail me the answer at [email protected]

 

[Counter Logic Gamer]

bro.... I find one thing contradicting in micrometer screw gauge does the fractionating scale have 1mm or 0.5mm length and are ther 50 or 100 divisions cuz david sang's book says 50 and 0.5 bt pople says 1 and 100?? which is correct?? URGENT HELP!!

 

[Mr.Physics]

About physics,
Can anybody tell me whats included in paper 1,4 and 6?

Btw we are gonna give paper 3 not 4 !
paper 3 is theory and paper 4 is coursework !!

 

[sj0007]

View attachment 50059
Guys could anyone help?! Especially (ii) I'm stuck wiz it

(i)Magnesium, iron, lead and silver (most to least)
(ii) Always the most reactive metals lose ions most readily........so that would be magnesium
(iii)I think silver would be the one that is the best oxidising agent since it would be the one that most readily accepts electrons

 

[sj0007]

Also, I wanted to know whether or not key words are really important..........coz from what I heard, it seems that keywords are the most important thing in biology...............plzzzz help

 

[maram23]

Well can anyome send me an attatchment to my email [email protected] with niology 2015 definitions aswell as Physics OL please

 

[Mr.Physics]

What is auxin ??