Year 12s: what will be the first way you research your future options? >>

AS Level Chemistry Redox Questions

D558C1ED-0002-40DD-8446-EC1A9ECC2D3B.jpg.jpeg

Hey guys, I don’t know how I’d go about answering these! Help would be appreciated : )

The roman numerals indicate the oxidation state.
For example with copper (ii) nitrate (v) copper must have a 2+ charge (metals form positive ions). The overall charge of the compound is 0 therefore the nitrate ion/s must add to a -2 charge. The question tells you that the ions have a -1 charge. Therefore there must be 2 nitrate ions bonded to the copper as 2×-1 is = -2. Now we need to work out the formula of the ion itself. The (v) indicates the oxidation state of the central atom of the ion - which is nitrogen. Nitrogen will have a +5 charge and the overall charge of the ion is -1 (give in question). You should know that each oxygem always has a oxidation state of -2 . To get from +5 to -1 you need to minus 6 6/2 = 3. Therefore there are 3 oxygen atoms in the nitrate ion. So your overall formula is :
Cu(NO3)2

Posted from TSR Mobile

(edited 6 years ago)

Reply 2

isitreallyjess

Thank you so much. This helped me a lot in my test!