Physics, Chemistry and Biology: Post your doubts here!

[rida.12.!!]

 

[Awesome12]

This is not actually a doubt but I need a little help
the problem is that my physics sir gave me a book named ' Explaining physics ' by Stephen Pople
that book is really good but he (sir) gave me the book temporarily I have to return it as soon as I can
I tried to go to a copy center copy the book but too expensive ( book is good thats why i need to copy and keep it )
If anyone here can really help me it would mean the world to me ( post a copy of the book here or link or something like that )
the book name is
Explaining Physics gcse Edition
by Stephen Pople
please post as soon as possible as board (IGCSE ) exams are really near
Thank You

Well you could get a second hand book priced well below the original price
Not as many people are willing to post an entire book on the net. After all, they are copyright. If you live in Pak, then you can get a pirate or a second-hand book easily. But if you are not, but have a relative in Pak, then tell them to send it for you. Stephen Pople has another book (Fundamental Physics); you can buy that book

 

[OneOfAKind]

In paper 6 (both bio and phy) they ask to plot graphs, is it necessary to start the graphs from 0 (X Axis Y Axis) or we can put that sign to show that the graph is not beginning with 0 and plot it? will they cut marks for it? ...

 

[Mai(M4!)]

what are the common apparatus asked for in paper 6 chemistry???

 

[Areeb Mohsin]

Well you could get a second hand book priced well below the original price
Not as many people are willing to post an entire book on the net. After all, they are copyright. If you live in Pak, then you can get a pirate or a second-hand book easily. But if you are not, but have a relative in Pak, then tell them to send it for you. Stephen Pople has another book (Fundamental Physics); you can buy that book

thanks mate
but i live in ksa, riyadh
but anyway thanks for the help, appreciate it

 

[Phoenix Blood]

Help.

 

[Phoenix Blood]

Why do branched isomers have a lower melting point/ boliling point than unbranched ones of the same molecular formula?

 

[Awesome12]

Why do branched isomers have a lower melting point/ boliling point than unbranched ones of the same molecular formula?

In branched molecules, the molecules are closer together, and make a compact shape. Thus less heat can be used to break the bonds.

 

[Heba A.Moety]

Hello! can anyone explain me the temperature changes with endothermic and exothermic reactions, PLZzz

 

[Heba A.Moety]

View attachment 39209
excuse me, but the answer for Ques4 a(ii) shouldnt it be that the forward reaction in equation one is endothermic and is favored by high temp. where as the forward reaction in equation 2 is exothermic that is why a high yield is obtained at low temp., plz correct me if i am wrong.

 

[Awesome12]

View attachment 39209
excuse me, but the answer for Ques4 a(ii) shouldnt it be that the forward reaction in equation one is endothermic and is favored by high temp. where as the forward reaction in equation 2 is exothermic that is why a high yield is obtained at low temp., plz correct me if i am wrong.

Read the equations again. They are not the same equations

 

[Heba A.Moety]

hey do we have to measure angles?!

 

[Heba A.Moety]

Read the equations again. They are not the same equations

yeah i'm aware of that, but still i think that the reason should be related to endo and exo reactions. if not plz expand on ur point of view.

 

[shoaib672002]

In paper 6 (both bio and phy) they ask to plot graphs, is it necessary to start the graphs from 0 (X Axis Y Axis) or we can put that sign to show that the graph is not beginning with 0 and plot it? will they cut marks for it? ...

Awesome12

 

[shoaib672002]

View attachment 39657
hey do we have to measure angles?!

Well IT DOES SAY NOT TO MEASURE OR CALCULATE ANGLES

 

[Heba A.Moety]

Well IT DOES SAY NOT TO MEASURE OR CALCULATE ANGLES

thnx, i just got confused by that answer .

 

[ZohaKhan]

Q2 part c
Q5
Q6
q8 part h,j,k
Please help me out asap

 

[Awesome12]

yeah i'm aware of that, but still i think that the reason should be related to endo and exo reactions. if not plz expand on ur point of view.

The endo and exo things are not even given. We can't assume that. And not every reaction has a forward reaction that is endo, and the backward reaction being exo. It can be the vice versa as well

 

[Heba A.Moety]

The endo and exo things are not even given. We can't assume that. And not every reaction has a forward reaction that is endo, and the backward reaction being exo. It can be the vice versa as well

yeah it is true i just assumed based on the case. which year is this let me check the marking scheme?

 

[Heba A.Moety]

Q2 part c
this should do for part c(i)
in c(ii)the answer should be that both contain a double bond. this is because a double bond characterize unsaturated alkenes as it can be broken to single bonds and more hydrogen atoms can be attached.


for ques 5 i think u hsould measure the distence between base line and spot(X) and then divide this by distance moved by solvent (solvent front) from base line.check i think u should get the answer.