Biology; Chemistry; Physics: Post your doubts here!

[snowbrood]

Yeah but its not mentioned if its in liquid or solid state so i did it on the basis of a solid ! ! But by assuming room temp then it should be reaction 1 ! that would be fastest !

under normal conditions it is liquid

 

[tania]

Where is the help wanted like the basic stuff or u have problem understanding the concepts !

yeah the concepts are very confusing

 

[..sacrifice4Revenge..]

guys can u give the answer wid refrence to the three conditions plz...
hurry plz

 

[snowbrood]

guys can u give the answer wid refrence to the three conditions plz...
hurry plz

answer to what

 

[scouserlfc]

Can u tell where u got this question 22speed22

 

[Hateefa]

well in o level u have to take physics whether u be a doc or engineer

ok thx...

 

[snowbrood]

Can u tell where u got this question 22speed22

which ques is he talking abt can anyone please tell me

 

[F husna]

Im not able to find cie o level chem and physics revision guide.hope some1 can help me.....

 

[CaptainDanger]

Im not able to find cie o level chem and physics revision guide.hope some1 can help me.....

(ALL NOTES) =) O-LEVEL 0R IGCSE + A-Level

 

[scouserlfc]

which ques is he talking abt can anyone please tell me

the same H2O2 one ! dont u remember !

 

[Ayesha Olakh]

Assalam-o-Allaikum and Hi everyone ,
hope u all are doin great !

Well as the topic says help for chemistry biology and Physics is available here that means that u can ask any mind blowing question or ask any question regarding a particular topic or ask abt any questions from Past paper or any of your text books. 8) :Yahoo!:

I made this topic so that people dont make many posts asking abt bio,physics or chemistry individually but they can post their reply here where it can be answered with ease and the members wont have to go searching for topics to help! !

So what are u waiting for now write ur questions here !
THANKS and Bye or Allah Hafiz ! :wink: :good:

What is always produced when aqueous copper sulfate is electrlysed?

 

[CaptainDanger]

What is always produced when aqueous copper sulfate is electrlysed?

Oxygen at anode and Copper at cathode...

 

[snowbrood]

guys can u give the answer wid refrence to the three conditions plz...
hurry plz

hey i gaved my answer wid referece to the three conditions didnt u notice that

 

[hassan100]

Q. following data shows decomposition of H2O2 at different condition.
1) 50cm3 H2O2 + 1.0G OF CuO
2) 25cm3 H2O2 + 25cm3 of H2O + 1.0g of CuO
3) 50 cm3 of H2O2 only

Explain in detail which reaction will be slowest and fastest? Why? Compare the reaction rate under 3 given conditions.

Plz answer wid the 3 CONDITIONS IN mind ..
thnx

Well, i think Option 1 would be the fastest reaction because it contains no water so the solution is concentrated . CuO is acting as a catalyst here so it will speed up the chemical reaction
In option 2 , water is added and less volume oh H2O2 is used so it is slower as water has diluted the solution nad there are less chances of frequent effective collisions
Option 3 is the slowest reaction, because no catalyst is there to lower the activation energy,thus decreasing the rate of reaction

 

[munir123]

Help!!! plzz provide me nuclear physics notes for o levels!!!plzzz

 

[scouserlfc]

Well, i think Option 1 would be the fastest reaction because it contains no water so the solution is concentrated . CuO is acting as a catalyst here so it will speed up the chemical reaction
In option 2 , water is added and less volume oh H2O2 is used so it is slower as water has diluted the solution nad there are less chances of frequent effective collisions
Option 3 is the slowest reaction, because no catalyst is there to lower the activation energy,thus decreasing the rate of reaction

Yup thats correct ! ! !

Help!!! plzz provide me nuclear physics notes for o levels!!!plzzz

Try raynotes type this in google and see !

 

[Dashing Cancerian]

ppl i need help for the vector one if anyone has got notes for that topic kindly post them.....

 

[aleezay]

@XPFmember: havnt u confused the 2 terms?? a solution is hypertonic to another solution when it has LESS water potential while hypotonic has GREATER water potential.recheck ths 4m the book..

 

[nightmaressana]

guys, did the bio paper pattern change slightly? because in sec b, the previous papers, we were given a choice of 3 or 4 questions and had to do 3. and now in section b, we have to do 2 compulsory questions and in section c are given a choice of one out of two? is it so? or maybe i downloaded the wrong paper.

And please, guys, can you please help me with the concepts of the speed of reaction chapter? how do we know when the products are going to increase in amount? please help as we havent done it.

 

[CaptainDanger]

guys, did the bio paper pattern change slightly? because in sec b, the previous papers, we were given a choice of 3 or 4 questions and had to do 3. and now in section b, we have to do 2 compulsory questions and in section c are given a choice of one out of two? is it so? or maybe i downloaded the wrong paper.

And please, guys, can you please help me with the concepts of the speed of reaction chapter? how do we know when the products are going to increase in amount? please help as we havent done it.

Yes the last part of theory paper has changed... They have Section C now, where you have to do one of the two questions...

For Chemistry read this, If you still have problems you can post then...