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# chemistry AS redox equation watch

1. I need help writing the half equations for these two reactions

ClO- → ClO3-, ClO- → Cl-

i wrote

Cl0- + 2H20 --> Cl03- + 4H+ + 4e-
2Cl0- + 4H+ + 4e- --> 2Cl- + 2H20

I though the answer was Cl0- --> Cl03- + 2Cl-

but it is 3ClO- → 2Cl- + ClO3-

can someone please explain this to me

Thanks
2. (Original post by zoedhin)
I need help writing the half equations for these two reactions

ClO- → ClO3-, ClO- → Cl-

i wrote

Cl0- + 2H20 --> Cl03- + 4H+ + 4e-
2Cl0- + 4H+ + 4e- --> 2Cl- + 2H20

I though the answer was Cl0- --> Cl03- + 2Cl-

but it is 3ClO- → 2Cl- + ClO3-

can someone please explain this to me

Thanks
Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
I'll post working
3. (Original post by notathuggee)
Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
I'll post working
Ohhh ok that makes sense! i didn't realise that the answer had to be balanced
4. (Original post by notathuggee)
Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
I'll post working
Can you help me with this one

a) PbO2 → Pb2+, Cl- → Cl2

Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20

but the answer is wrong can you tell me why?

PbO2 + 4H+ + 2Cl- → Pb2+ + 2Cl- + 2H2O

Thanks
5. (Original post by notathuggee)
Well the answer is balanced and the oxidation state of chlorine in ClO3- is +5
I'll post working
6. (Original post by zoedhin)
Can you help me with this one

a)PbO2 → Pb2+, Cl- → Cl2

Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20

but the answer is wrong can you tell me why?

PbO2 + 4H+ + 2Cl- → Pb2+ + 2Cl- + 2H2O

Thanks
That correct answer isn't balanced in charge???
2+ on LHS and 0 on RHS

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7. (Original post by C0balt)
That correct answer isn't balanced in charge???
2+ on LHS and 0 on RHS

Posted from TSR Mobile
that stems from the Pb tetracation being unstable and forming the Pb dication
8. (Original post by notathuggee)
that stems from the Pb tetracation being unstable and forming the Pb dication
Is that in AS?

Posted from TSR Mobile
9. (Original post by zoedhin)
Can you help me with this one

a) PbO2 → Pb2+, Cl- → Cl2

Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20

but the answer is wrong can you tell me why?

PbO2 + 4H+ + 2Cl- → Pb2+ + 2Cl- + 2H2O

Thanks
pic should be attached
Attached Images

10. (Original post by notathuggee)
pic should be attached
Ohh ok im a bit confused tho

11. (Original post by notathuggee)
pic should be attached
is it

Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20
or

Pb02 + 4H+ + 2cl- --> Pb2+ +2cl- + 2H20
12. (Original post by zoedhin)
Pb02 + 4H+ + 2cl- --> Pb2+ +cl2 + 2H20
You've got 2Cl- on both sides!

There's no oxidation going on.

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