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IGCSE CHEMISTRY DOUBTS HERE !!!!

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Vin:
I hope I'm right.

1. Ce = 140g

n = 4.2/140
=0.03 moles

2. 5.16 - 4.2 = 0.96 g

3. moles of O2

n = 0.96/ (16+16)
= 0.03 moles

4. ratio = 1:1

5. Ce + O2 ---> CeO2

Formula = CeO2

~Dazzling Star~:

--- Quote from: Vin on January 12, 2011, 07:02:42 am ---I hope I'm right.

1. Ce = 140g

n = 4.2/140
=0.03 moles

2. 5.16 - 4.2 = 0.96 g

3. moles of O2

n = 0.96/ (16+16)
= 0.03 moles

4. ratio = 1:1

5. Ce + O2 ---> CeO2

Formula = CeO2

--- End quote ---
hmmmm,i think it should be done like this :
1 . n=m/Mr
     n=4.2/75
     n=0.056 moles
2 . mass of reacted Oxygen=5.96-4.2=0.96g
3 . n=m/Mr
     n=0.96/(16*2)=0.03 moles
4 . 0.056:0.03=2:1
5 . CeO
do u agree?

Vin:
Hmm I think the Mr for Ce is 140g in the periodic table. :/ atomic number 58

Most UniQue™:
M/j 2005 p62 Q8

Plz help got exam tomorrow Thanks in advance:D

The Golden Girl =D:
can ya give me a link of the paper.

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