• We need your support!

    We are currently struggling to cover the operational costs of Xtremepapers, as a result we might have to shut this website down. Please donate if we have helped you and help make a difference in other students' lives!
    Click here to Donate Now (View Announcement)

Chemistry: Post your doubts here!

Messages
253
Reaction score
289
Points
73
As-salam-mu-alikum,

This is Walid. Can anyone please tell me that , can we appear as a private student for CAMBRIDGE INTERNATIONAL AS / A Levels CHEMISTRY?

Please reply as soon as possible! I'll be waiting for the reply!

Thanks.

JAZA-KALAH-KHAIR!
 
Messages
675
Reaction score
862
Points
103
As-salam-mu-alikum,

This is Walid. Can anyone please tell me that , can we appear as a private student for CAMBRIDGE INTERNATIONAL AS / A Levels CHEMISTRY?

Please reply as soon as possible! I'll be waiting for the reply!

Thanks.

JAZA-KALAH-KHAIR!


Yeah, you can.
 
Messages
134
Reaction score
108
Points
53
AOA EVERYBODY

This question does not make sense to me .The answer is C.I have eliminated options A and D by myself.What really confuses me is how polyethene melts over a range of temperature ,and paper does not.
Mixtures are supposed to melt over a range of temperature right?

6 A substance commonly found in the house or garden has the following properties.
• It is combustible.
• It is an electrical insulator.
• It melts over a range of temperature.
What could the substance be?
A brass
B paper
C poly(ethene)
D silicon(IV) oxide


Please can anyone explain the concept tested in this question?

Thanks!
 
Messages
675
Reaction score
862
Points
103


MgBr2

Mg = -2.38
Br2 = -1.07
O2 = -0.40
H = 0.00


AgF
Ag = 0.8
F = 2.87
O2 = -0.40
H = 0.00

FeSO4
Fe = -0.44
SO4 = 0.17
O2 = -0.40
H = 0.00


According to the values:

Anode:
MgBr2: Br2
AgF: O2
FeSO4: O2


Cathode

MgBr2: H2
AgF: Ag
FeSO4: H2

Get it?
You just need to see the values.
If you don't get the chapter, i.e how to choose values, I'll suggest you read up the chapter on chemguide. Very good stuff there and very well explained.
 
Messages
158
Reaction score
55
Points
38
MgBr2

Mg = -2.38
Br2 = -1.07
O2 = -0.40
H = 0.00


AgF
Ag = 0.8
F = 2.87
O2 = -0.40
H = 0.00

FeSO4
Fe = -0.44
SO4 = 0.17
O2 = -0.40
H = 0.00


According to the values:

Anode:
MgBr2: Br2
AgF: O2
FeSO4: O2


Cathode

MgBr2: H2
AgF: Ag
FeSO4: H2

Get it?
You just need to see the values.
If you don't get the chapter, i.e how to choose values, I'll suggest you read up the chapter on chemguide. Very good stuff there and very well explained.

the values are all positive
+1.07 for br2
+0.40 for o2
+2.87 for f2

then how come, under the same conditions br2 is released rather than o2.

the value of both halogen are more positive than that of 02.

there is another reaction involving the release of 02 whose value is +1.23 and is more than that of br2 but less than f2

h20 = o2 + 4h+ + 4e

is it because this reaction is occuring that br2 is being released rather than 02 or is the first reaction occuring and i am missing something?
 
Messages
663
Reaction score
282
Points
73
can anyone solve this please and also let me know the reason for it ? please its urgent :)
 

Attachments

  • Capture.PNG
    Capture.PNG
    51.8 KB · Views: 12
Top