NEAP 2006 Question. (1 Viewer)

[Divinity_]

Answer says D; just wondering if anyone can explain it for me.

 

[GUSSSSSSSSSSSSS]

here chlorine gas is reducing to form chloride ions ------> less chlorine gas and more chlorine ions
nickel solid is oxidising to form nickel ions --------> less nickel solid and more nickel ions

thus you can tell that the CONCENTRATION of chlorine ions increases, but the CONCENTRATION of chlorine gas decreases
and
the CONCENTRATION of nickel ions increases, but the mass of nickel solid (electrode) decreases

since the platinum electrode takes no part in the reaction there is no change to it's mass


xD

 

[Divinity_]

zomg, i didn't realise it's that easy -_-

thanks angus

 

[eriito]

Could you send me a copy of the paper please?

 

[rufous]

The chlorine is being reduced because it has a greater attraction for electrons than does nickel - hence the transfer of electrons to the chlorine half cell (at the same a time an internal flow of ions between the half cells balances this flow of charge due to the electrons in the wire). I cannot see how the concentration of chlorine can decrease as it is constantly replaced via the flow of chlorine in the gas electrode. Yes, it is consumed but the system is not a closed one. Question could therefore be confusing for an enquiring student.