Biology; Chemistry; Physics: Post your doubts here!

[amna shah]

1) how to focus the image made by a converging lens in camera ??

2) Explain in terms of bond breaking and bond making why reaction of (some reaction) is exothermic ?? how to answer these type of Q's ??

 

[ayeshaK]

1) how to focus the image made by a converging lens in camera ??

2) Explain in terms of bond breaking and bond making why reaction of (some reaction) is exothermic ?? how to answer these type of Q's ??

Bond breaking means endothermic and bond forming means exothermic !! And thus u need to write that in this exothermic reaction the overall bond forming is greater than bond breaking so the overall reaction is exothermic and more energy is released in exothermic reactions

 

[SalmanPakRocks]

1) how to focus the image made by a converging lens in camera ??

2) Explain in terms of bond breaking and bond making why reaction of (some reaction) is exothermic ?? how to answer these type of Q's ??

1) By adjusting the length of Lens from focus point.
2) It's exothermic because more amount of bonds are made which releases more energy than which is absorbed while bond breaking.

 

[GetSomeLife]

1) how to focus the image made by a converging lens in camera ??

2) Explain in terms of bond breaking and bond making why reaction of (some reaction) is exothermic ?? how to answer these type of Q's ??

1) By adjusting the length of Lens from focus point.

2) The reaction is exothermic because the amount of energy released when making the bonds is greater than the amount of energy required when breaking them!

It doesn't always depend on the number of bonds but rather the energy required to break/make them

 

[ashiqbal]

they torture us like hell

u can write that aadd charcoal to remove indicator, instead of repeating the experiment!

 

[ashiqbal]

1) how to focus the image made by a converging lens in camera ??

2) Explain in terms of bond breaking and bond making why reaction of (some reaction) is exothermic ?? how to answer these type of Q's ??

Energy Released in bond Making is greater than the energy Absorbed in bond Breaking!

 

[mohammadusman96]

Plz tell me good chem ATP notes?? and any1 with guess paper of physics n chemistry??

 

[multixamza01]

Plz tell me good chem ATP notes?? and any1 with guess paper of physics n chemistry??

No guesses for chemistry and physics!!

 

[convent2012]

Plz tell me good chem ATP notes?? and any1 with guess paper of physics n chemistry??

sciences r unpredictable

 

[multixamza01]

A 4 mark question is expected on Star Formation this year for Physics .

 

[ayeshaK]

u can write that aadd charcoal to remove indicator, instead of repeating the experiment!

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 !!

 

[hafsaaamer]

Will we get A on 80% or 85% ???

 

[hafsaaamer]

please reply quick if you guys know

 

[ayeshaK]

Will we get A on 80% or 85% ???

80% and above A
90% above A*

 

[hafsaaamer]

80% and above A
90% above A*

Thankyou but are you 100% sure? my teacher was telling me its on 85%
:/ :/

 

[ayeshaK]

Thankyou but are you 100% sure? my teacher was telling me its on 85%
:/ :/

Yes sure !

 

[hafsaaamer]

YAAAAAAAAAAAAYYYYYYYY thanks. God bless you you angel

 

[multixamza01]

Thankyou but are you 100% sure? my teacher was telling me its on 85%
:/ :/

it's on 80 + for Sciences and other Major subjects .
But that's not definite , it depends on how high or low the percentile is set.

 

[ayeshaK]

Can anybody please explain me about the nitrogen cycles ?

 

[multixamza01]

Can anybody please explain me about the nitrogen cycles ?

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