Biology; Chemistry; Physics: Post your doubts here!

[***amd***]

It does? Are you sure?

u dont know?

 

[funky brat]

Increasing the mass of catalyst per se, does not increase reaction rate. Reaction rate is increased mainly through increasing the surface area of the catalyst. If you keep the mass of catalyst constant and mechanically alter its shape you can:
1) if you reduce the surface area, reduce reaction rate
2) If you increase the surface area, increase the reaction rate.

You cannot make the broad claim that reaction rate is affected by mass of catalyst. This is not technically correct.

That's what I believe.

Exactly.

 

[funky brat]

u dont know?

I knew this. But the way he said, I thought I had been wrong always.

 

[Maganius]

Exactly.

Mera Q bhe answer kr dein

How to determine the color change in Titraion reactions?

 

[funky brat]

u dont know?

And we are talking about increasing the quantity of catalyst not the purpose of it.

 

[funky brat]

Mera Q bhe answer kr dein

How to determine the color change in Titraion reactions?

I performed titartions so I find it easy.
Weak bases kat kiye we use methyl orange which is pale yellow, in base and clolourless at neutral point and red when acid in excess.
Otherwise phenpoph is cloulress in acid and pink in alkali.

 

[exploded diper]

Increasing the mass of catalyst per se, does not increase reaction rate. Reaction rate is increased mainly through increasing the surface area of the catalyst. If you keep the mass of catalyst constant and mechanically alter its shape you can:
1) if you reduce the surface area, reduce reaction rate
2) If you increase the surface area, increase the reaction rate.

You cannot make the broad claim that reaction rate is affected by mass of catalyst. This is not technically correct.

That's what I believe.

I meant like adding a catalyst....

 

[Maganius]

I performed titartions so I find it easy.
Weak bases kat kiye we use methyl orange which is pale yellow, in base and clolourless at neutral point and red when acid in excess.
Otherwise phenpoph is cloulress in acid and pink in alkali.

Na kr :O
Then it's freakin' easy -_- I know the color of indicators, fazul mein tension le rha hon

Btw, would you like to gimme few tips before I leave?

 

[funky brat]

Na kr :O
Then it's freakin' easy -_- I know the color of indicators, fazul mein tension le rha hon

Btw, would you like to gimme few tips before I leave?

The best tip is to read everything carefully and understand, then answer. Knowledge to sab kay pass he hota hai.
Anyways best of luck. Pray for everyone. Insha'Allah we'll do well.

 

[Maganius]

The best tip is to read everything carefully and understand, then answer. Knowledge to sab kay pass he hota hai.
Anyways best of luck. Pray for everyone. Insha'Allah we'll do well.

Thanks ^_^
Sure thing N Yep, InshaAllah, everyone will get good grades.

*Poof* Maganius Vanishes.

 

[***amd***]

http://papers.xtremepapers.com/CIE/...l O Level/Chemistry (5070)/5070_s13_qp_42.pdf
Q3

 

[peacce]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Chemistry (5070)/5070_w13_qp_41.pdf
Q.8 part i
mine answer is 2 n ms says 3.. how ?? ***amd***

 

[***amd***]

http://papers.xtremepapers.com/CIE/Cambridge International O Level/Chemistry (5070)/5070_w13_qp_41.pdf
Q.8 part i
mine answer is 2 n ms says 3.. how ??

Atomic mass of K + atomic mass of I + (x * atomic mass of O) = 214
39 + 127 + 16x = 214
166 + 16x = 214
16x = 214-166 = 48
x = 48/16 = 3

 

[peacce]

Atomic mass of K + atomic mass of I + (x * atomic mass of O) = 214
39 + 127 + 16x = 214
166 + 16x = 214
16x = 214-166 = 48
x = 48/16 = 3

thnx man

 

[Faizan Muhammmad]

The best tip is to read everything carefully and understand, then answer. Knowledge to sab kay pass he hota hai.
Anyways best of luck. Pray for everyone. Insha'Allah we'll do well.

Isee ka hee to masla hai, koee ajeeb colour waghaira day dia to kia karna hai

 

[Bhaijan]

Hi guys I have an extremely important question.
From 5070_w13_qp42
In this question, Potassium Manganate VII is titrated with Iron II in conical flask. As Iron II is green, the colour should change from GREEN to colorless. BUT the solution changes from Green to Pink. When Potassium Manganate (VII) is reduced, it becomes colorless. but here, its becoming pink, what's going on?


And here are the answers:

 

[asadalam]

Hi guys I have an extremely important question.
From 5070_w13_qp42
In this question, Potassium Manganate VII is titrated with Iron II in conical flask. As Iron II is green, the colour should change from GREEN to colorless. BUT the solution changes from Green to Pink. When Potassium Manganate (VII) is reduced, it becomes colorless. but here, its becoming pink, what's going on?
View attachment 42310

And here are the answers:
View attachment 42311

KMnO4,goes into excess right after all the iron has been fully oxidised.So there is a pink solution due to it going into excess.

 

[Bhaijan]

KMnO4,goes into excess right after all the iron has been fully oxidised.So there is a pink solution due to it going into excess.

Yeah but its talking about the end solution, it doesn't mention that the potassium manganate was added in excess.

 

[asadalam]

Alright guys,best of luck for the paper,i'm heading to the center..

 

[funky brat]

Yeah but its talking about the end solution, it doesn't mention that the potassium manganate was added in excess.

This is what we were talking about yesterday when they ask you about the colour change at the end point, they are asking about the colour in excess.