Qualification > Sciences
Chemistry Help HERE ONLY !!
AS girl:
An alloy contains zinc and Copper . A small sample of this alloy was dissolved in acid to give a soluion containing zinc and copper ions.
Explain what would happen when an excess of each of the following reagents is separatly added to this solution.
i) Iron Fillings
effervescenses-bubbles of colourless gas. With lighted splint it pops (Hydrogen)
------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------ [2]
ii) Sodium Hydroxide
------------------------------------------------------------------------------------------
zinc-white precipetation soluble in excess
------------------------------------------------------------------------------------------ [2]
Copper-blue ppt becomes soluble in excess solution changes to deep blue(royal)
I'm not sure of the answer!!
gonnagetana:
thats interesting, i got a whole bunch of different answers
archangel:
--- Quote from: IG girl on May 26, 2009, 10:58:40 pm ---
An alloy contains zinc and Copper . A small sample of this alloy was dissolved in acid to give a soluion containing zinc and copper ions.
Explain what would happen when an excess of each of the following reagents is separatly added to this solution.
i) Iron Fillings
effervescenses-bubbles of colourless gas. With lighted splint it pops (Hydrogen)
------------------------------------------------------------------------------------------
------------------------------------------------------------------------------------------ [2]
ii) Sodium Hydroxide
------------------------------------------------------------------------------------------
zinc-white precipetation soluble in excess
------------------------------------------------------------------------------------------ [2]
Copper-blue ppt becomes soluble in excess solution changes to deep blue(royal)
I'm not sure of the answer!!
--- End quote ---
the first one:
the iron fillings would displace the copper while the iron filings would be displaced by zinc, bcoz it is more reactive than iron.
brown red solid will be found on the bottom on the beaker.
second one:
zinc- white ppt. souble in excess giving colourless solution
copper - light blue ppt. formed in excess
[blue ppt. soluble in excess giving dark blue solution is for aqueous ammonia]
i hope its correct and this helps =)
zubair_slipknot:
Reactivity table /\
|
Potassium |
Sodium |
Calcium |
Magmesium |
aluminium |
carbon |
zinc |
iron |
tin | Increasing of reactivity
lead |
hydrogen |
copper |
silver |
gold |
platinum |
Sorry could not draw a good arrow for the increasing of reactivity...hope this helps
sweetsh:
I know it like this
K
Na
Li
Ca
Mg
Al
Zn
Fe
Sn
Pb
Cu
Ag
Au
Pt
Navigation
[0] Message Index
[#] Next page
[*] Previous page
Go to full version