Biology; Chemistry; Physics: Post your doubts here!

[ayeshaK]

after result in august i guess, which is 13 august

Oh yeah but maths paper is here but without mark scheme

 

[ashiqbal]

Oh yeah but maths paper is here but without mark scheme

han, mujhe bhi yehi hairani ho rahi thi yeh kahan sai aaya!

 

[ayeshaK]

han, mujhe bhi yehi hairani ho rahi thi yeh kahan sai aaya!

Oh well in schools if they have extra papers they give it to the school admin !

 

[mrroland]

Dear Physics Students,

Check out fuchunphysics.wordpress.com

This blog contains teaching videos for Physics O' Level syllabus.
Chapters uploaded include:
1) Measurements
2) Kinematics
3) Dynamics
4) Mass, Weight and Density
5) Turning Effect of Force
6) Energy, Work and Power
7) Pressure
8) Kinetic model of matter

The teaching videos for the remaining chapters will be posted soon.

 

[ashiqbal]

Oh well in schools if they have extra papers they give it to the school admin !

usually there are no extra paper! but i guess that is the only plausible scenario.

 

[Tuba noor]

what will be oxidation state of calcium nitrate Ca(NO3)2
and
(NH4)2 CO3 ????

 

[MustafaMotani]

what will be oxidation state of calcium nitrate Ca(NO3)2
and
(NH4)2 CO3 ????

Oxidation state FOr both comPounds... ?? :S

Ca oxidation state is +2
and NH4 oxidation state is +1

 

[Tuba noor]

yes oxidation state for both compounds.
what will be oxidation state of calcium nitrate
(1) Ca(NO3)2
and
(2) (NH4)2 CO3 ????

 

[Snowysangel]

Does anyone have physics notes?

 

[nak shay]

will the june papers be available before next week??


thank you

 

[scouserlfc]

will the june papers be available before next week??


thank you

Nah it always after exams and btw why are people so excited to get their hands on the June papers what so cool about them ???

 

[ashiqbal]

Nah it always after exams and btw why are people so excited to get their hands on the June papers what so cool about them ???

i was present in the june exams, that's y!

 

[KyleoAhsan]

yes oxidation state for both compounds.
what will be oxidation state of calcium nitrate
(1) Ca(NO3)2
and
(2) (NH4)2 CO3 ????

Both compounds have a oxidation number of 0
That is because

Ca has a charge of +2 and NO3 has a charge of -1
So there are two nitrate ions joined to one Calcium ion so 2 + 2(-1) = 0

Likewise,
NH4 ion has a charge of +1 and CO3 has a charge of -2, Since there are 2 ammonium ions, 2(+1) + (-2) = 0

So in both cases it adds up to 0 !

 

[ali jahanzeb]

can u plzzz tell me the best way 4 the preparartion of my Olevel exams in this Oct/Nov session and the book u prefr
I have already covered the whole course

 

[ali jahanzeb]

i was present in the june exams, that's y!

wht about me who s going to appear in exams in November or

 

[Tuba noor]

Both compounds have a oxidation number of 0
That is because

Ca has a charge of +2 and NO3 has a charge of -1
So there are two nitrate ions joined to one Calcium ion so 2 + 2(-1) = 0

Likewise,
NH4 ion has a charge of +1 and CO3 has a charge of -2, Since there are 2 ammonium ions, 2(+1) + (-2) = 0

So in both cases it adds up to 0 !

thnku

 

[ali jahanzeb]

Salam
I was revising my course and faced a few problms in the following topics
1 polymerisation 2 electroplating 3 titration

 

[scouserlfc]

Salam
I was revising my course and faced a few problms in the following topics
1 polymerisation 2 electroplating 3 titration

So whats the problem in these topics like single them out

 

[arshadphysics]

explain why an electric bell work when connected to a low voltage a.c supply instead of a battery ?

 

[Haris Bin Zahid]

scouserlfc: How to calculate change in velocity?
E.g. if an airplane is flying at 500 km/h due west. It then changes its direction to east and now its speed is 400 km/h. What would be its change in velocity??????? Would it be 100 or 900? Plz help.