# cementing metals



## jimmyreece (Mar 3, 2011)

can somebody clearly define 'cementing metals'.is it just a term used when a paticular metal is pushed out of solution and cemented on to another metal or is there more to it than that


----------



## lazersteve (Mar 4, 2011)

The term 'cement' has a few meanings according to who you ask.

1: The name given to silver that has been displaced from a silver nitrate solution by copper metal. The name is derived from the fact that the silver appears gray like 'cement'.

2: A term used to describe the process of displacing a metal from a solution with a metal higher up in the activity series than the metal to be displaced.

Here's one version of an activity series (aka Reactivity) chart:







and a more detailed one found at wiki:

Wiki Reactivity Series

Metals higher up in the chart will 'cement' or displace metals lower in the chart from a solution. There are some exceptions. I once read somewhere that aluminum won't cement nickel out of an acidic solution.

The general reaction for copper displacing or 'cementing' silver out of silver nitrate is :

Cu + 2AgNO3 --> 2 Ag + Cu(NO3)2

The copper goes into the nitrate solution and the silver comes out as a solid.

Good question, I'm going to add this information to the General Reaction List.


----------



## jimmyreece (Mar 7, 2011)

thanks steve. can you identify the different metals being cemented out of a solution? you said the grey is silver hence the term "cemented"but ive had the colors of copper,black, white.brown and green. some being cemented or bonded to metals still in solution(copper,black,green). while the white,black(black powder isnt always gold) and brown would be a fine powder settling on the bottom. maybe you can give me a small list of different causes for different colors for most cases. that info would be a great help that i can add to my notes to help me confirn my own thinking or maybe even highlight it to another cause or metal
im sure this a common situation with many other newbies who are scratching there head with the same question


----------



## joem (Mar 7, 2011)

Ok (yes I have done the search) and since this is a thread to post this; is this cementing appropriate to create a waste material safe on the environment. I just want to clear it up in my mind on one thread.

Start with an A/P solution
can add copper to drop gold (this we know)
can add iron to drop copper (this we know)
what can be added to drop iron, Zinc ( is this correct)?
Which metal above iron is safe to be in the solution when disposing and Is adding sodium bicarbonate the last step to make a safe to dipose waste product? And which metal above iron is easy to get? Would sea salt work being 30% sodium? or charcol?

Please definitely correct me where I am wrong


----------



## glondor (Mar 7, 2011)

If I read the reactivity series chart correctly Aluminium will displace zinc.

Long winter eh Joem. Need a little spring.

Edited to add comment


----------



## joem (Mar 7, 2011)

glondor said:


> If I read the reactivity series chart correctly Aluminium will displace zinc.
> 
> Long winter eh Joem. Need a little spring.
> 
> Edited to add comment



Yes I see the zinc and Al, that's why I ask. But I am also looking for safe, I guess cheap, and readily available product. I am looking for an end result must be totally neutralized.

:evil: winter :evil: 
This weekend we had 1/4 of rain ontop of the snow and then it all froze solid that night. My favourite colour is green not white.


----------



## jimdoc (Mar 7, 2011)

joem said:


> :evil: winter :evil:
> This weekend we had 1/4 of rain ontop of the snow and then it all froze solid that night. My favourite colour is green not white.



I think you live a little too far north then.

Jim


----------



## joem (Mar 7, 2011)

jimdoc said:


> joem said:
> 
> 
> > :evil: winter :evil:
> ...



Not as far as noxx but still too far.
My wife wants to move to a all warm all the time climate.


----------

