Edexcel Official Chemistry Paper1:Core Inorganic and Physical Chemistry - 27th of May

Can anyone help me with this question please?
(topix 3 redox)

7. Write balanced equations for these redox reactions. State which element is oxidized and which is reduced in each example.
a) Fe and Br2 to give FeBr3

Overall equation: ………………….

Element oxidized: …………………

Element reduced: ………………

I know that Fe has oxidized because its oxidation state went from 0 to 3+

and that Br has been reduced as its oxidation state went from 0 to -1 (single atom)

And for the half equations i got: Fe ---> Fe^3+ + 3e^- & 3e^- + 3Br ----> Br3^-

same number of electrons in both half equations so it should make

Fe + 3Br ----> Fe^3+ + Br3^-

but the mark scheme says:2Fe(s) + 3Br2 (l) ----> 2FeBr3(s)

Can someone explain what i did wrong? is it because i changed the Br2 into Br?

Hello everyone!Could anyone please explain me why the answer is B ?- A sample of swimming pool water contains 0.482 ppm of chlorine. This is equal to a percentage of:A. 0.000482B. 0.0000482C. 0.00000482D. 0.000000482

Yes that was the mistake because bromine MOLECULES(Br2) are reduced, not bromine atoms.

Could someone explain what dative covalent bonding is? Thank you. 😊


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Could someone explain what dative covalent bonding is? Thank you. 😊

Posted from TSR Mobile

Thanks for your help!
I have one question tho say an atom doesn't reduce or oxidize it stays the same. Do i have to make a half equations for it? example F2 + H2O ---> HF + O2 I know that the oxygen has oxidized and the F2 has reduced but hydrogen stays the same. do i just make half equations on F2 and O2 and ignore H2 but include it in the overall equation?

No. hydrogen stays the same so they are spectator ions. you dont include them in the overall ionic equation. the overall ionic equation would be: 2o^2- +2f2--->4f^- +o2

Doing an all nighter?

Actually its not that man. I'm from Bangladesh and here it's 7 in the morning. Exam starts form 10:30 so im up for some last minute revision.

Oh Okay, So are we doing the same paper? Im in the UK

Is it no Hess's cycle in the new spec ?

hess cycle definitely WON'T be on today's paper, but may be in the Paper 2 on the 10th of June.

Yo whats the enthalpy change of the alkane with c h2 o2,

And whats the mutiple choice answer of the reforming

but it was