Hi Any chance of walk through of Set 1 and Set 2 chempapers? Would be amazing if paper 1 for both sets were done before the exam on the 13th. Would help with some of the maths stuff, in particular.
For the ionic equation when u add NH3 (eg to Cu2+), do you include NH3 or OH- as the reacting species? End of of practice paper set one has confused me :(
For the Cu2+ with excess NH3, should we use the overall equation instead of the second step (from the precipitate to the complex ion) since its more clearer that 4 H20 ligands are being replaced?
Niamh Milligan OCR issued a statement earlier this year clarifying it is actually purple, however often forms mixed complexes with other ligands and appears green. Not ideal I know
An explanation I've seen for the formation of hydroxides with NH3(aq) is that NH3(aq) (NH3 dissolved in water) is the same as NH4OH, which is where the OH- ions come from. Is this similar to your 'acidity' reaction explanation?
Hi
Any chance of walk through of Set 1 and Set 2 chempapers? Would be amazing if paper 1 for both sets were done before the exam on the 13th. Would help with some of the maths stuff, in particular.
This would be great! Especially for the multiple choice as the mark schemes don't into detail!
Could you please do this. It would be really helpful. Thank you
for NH3 reactions, can you write it using non-complex formulae like you did with OH-, or is that not acceptable?
For the ionic equation when u add NH3 (eg to Cu2+), do you include NH3 or OH- as the reacting species? End of of practice paper set one has confused me :(
cherry bruce I’m really confused on the exact same thing right now from the same question. Would u be able to explain by any chance now ? Thanks
For the Cu2+ with excess NH3, should we use the overall equation instead of the second step (from the precipitate to the complex ion) since its more clearer that 4 H20 ligands are being replaced?
Hi! Can i just double check, we learnt Cr(H2O)6 is green not purple?
Niamh Milligan OCR issued a statement earlier this year clarifying it is actually purple, however often forms mixed complexes with other ligands and appears green. Not ideal I know
Thank you so much! :)
Niamh Milligan You're welcome. I think they'll have to be flexible on this one :)
@machemguy +machemguy can you make a video on ksp (solubility product) please, would be highly appreciated have a major exam next thu
An explanation I've seen for the formation of hydroxides with NH3(aq) is that NH3(aq) (NH3 dissolved in water) is the same as NH4OH, which is where the OH- ions come from. Is this similar to your 'acidity' reaction explanation?
Glacier mints Sure is. Those OH- ions then remove H+ from the molecules.
thanks for the video but Cr3+ is a green solution not VIOLET
CFC 9 I take it your teacher hasn't read the update from OCR?
its states this in the cgp text book
CFC 9 Which was written before the update was posted. I'll tweet the link