Any Type of Doubts in ENg Phy Chem Bio or Math....Ask me here!!!

[Fatima18]

also plz post for phy as well as eco........

Did you check www.freeexampapers.com ?

 

[examkiller]

iron (ii ) ions in fe0 react with oxygen to form fe2O3 ?which statement about the iron is correct ?
1. iron (ii) ions are oxidised because they gain oxygen
2. iron ( ii) are reduced because they lose oxygen
are oxidsed because they gain oxygen
are reduced because they lose oxygen ?
which one is it, and how to find the answer ?

 

[To2a Bahaa]

iron (ii ) ions in fe0 react with oxygen to form fe2O3 ?which statement about the iron is correct ?
1. iron (ii) ions are oxidised because they gain oxygen
2. iron ( ii) are reduced because they lose oxygen
are oxidsed because they gain oxygen
are reduced because they lose oxygen ?
which one is it, and how to find the answer ?[/quo
The answer is A since the number of oxygen atom increases from FeO to Fe2O3

 

[Shepard97]

Easy xDD
it's a redox reaction...

 

[Fatima18]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w07_qp_1.pdf
Hey guys...number 33 is supposed to be D...however, isn't plating iron with zinc also a way of preventing rusting?

 

[Shepard97]

http://www.xtremepapers.com/papers/CIE/Cambridge IGCSE/Chemistry (0620)/0620_w07_qp_1.pdf
Hey guys...number 33 is supposed to be D...however, isn't plating iron with zinc also a way of preventing rusting?

Already answered that. in other topic

 

[examkiller]

Thnks , btw i was just confused because oxi is loss of electrons, and i thought that for i.e 2cu---> cu2 since it loses electrons, however i got it wrong, is oxi basically the adding of electrons ? so if its 2X----> its gonna be x2 ?

 

[Fatima18]

Already answered that. in other topic

Thanx!

 

[somya]

i have a few doubts... plz answer em asap!

 

[Fatima18]

i have a few doubts... plz answer em asap!

Letter D for the first one...Impurity lowers the melting point and raises the boiling point.

 

[Fatima18]

i have a few doubts... plz answer em asap!

Letter D for the last one too.

 

[somya]

Fatima18: what about the second one??

 

[Fatima18]

Fatima18: what about the second one??

Sorry for that.I'm not doing Physics, hence I replied chem questions only.

 

[smart_boy]

Calculate the amount fr product formed per unit time.....or calculate the usage of product per unit time

The reaction is 2NO + O2 --> 2NO2. If you see, all the chemicals are gases... I only know that NO2 is brown in colour and the rest of the gases are colourless... so how to calculate the amount fr product formed per unit time.....or calculate the usage of product per unit time...???? The question asks for the practical details and procedure...

 

[theexamfreak]

Did you check www.freeexampapers.com ?

ya ofcourse i did!!!!

 

[somya]

Sorry for that.I'm not doing Physics, hence I replied chem questions only.

thanks anyway!

 

[somya]

physics doubt!

 

[Shepard97]

I'm not so sure.. but most probably it's A or D..

 

[somya]

I'm not so sure.. but most probably it's A or D..

it's D, but how??

 

[Shepard97]

See somya..
There is no friction ... so nothing is opposing the speed of the ball ..
hence it is going faster and faster ... hence D.