Aluminum we use

[umer007]

Is the aluminum we use in real life the actual Al(s) from the periodic table or is it like Al2O3, since there is oxygen everywhere so it changes? If it is the Al2O3, how would this interfere with the results from a experiment where a strip of Aluminum was part of the reactant but in the eqn its Al(s).

 

I did experiment 2Al(s) + 3CuCl2.2H20 (aq)---> 3Cu(s) + 2AlCl3 + 6H20

 

THe purpose was to find how much copper was produced. So if its not Al(s) that I used but Al2O3, how would this affect the amount of copper produced. Ne ideas need help.

 

Also could someone plz tell me what deionized water is. Is it pure water containing nothing else. Or does it have some minerals in it.

 

Thx in advance

[budullewraagh]

it's mostly aluminum with some oxide impurity. if it's wet, you'll have some hydroxide impurity.

"I did experiment 2Al(s) + 3CuCl2.2H20 (aq)---> 3Cu(s) + 2AlCl3 + 6H20"

if you had the oxide of aluminum, it would hydrolyze to form the hydroxide. you wouldn't get copper.

 

deionized water is just that: DE-IONIZED water. there are no ions dissolved in it. it is completely pure.

[coquina]

Is the aluminum we use in real life the actual Al(s) from the periodic table or is it like Al2O3' date=' since there is oxygen everywhere so it changes? If it is the Al2O3, how would this interfere with the results from a experiment where a strip of Aluminum was part of the reactant but in the eqn its Al(s).

 

I did experiment 2Al(s) + 3CuCl2.2H20 (aq)---> 3Cu(s) + 2AlCl3 + 6H20

 

THe purpose was to find how much copper was produced. So if its not Al(s) that I used but Al2O3, how would this affect the amount of copper produced. Ne ideas need help.

 

Also could someone plz tell me what deionized water is. Is it pure water containing nothing else. Or does it have some minerals in it.

 

Thx in advance[/quote']

 

There are many alloys of Aluminum, there are ones that are made for forging, and for extruding - "6061" is the most commonly used for machining - It is 1.% Mg, .6%Si, .2 Cu & .2 Cr - the rest is AL. "6063" is used for sheet metal work because you can bend it and it won't crack. It is .7 Mg .4Si, and .3Fe.

 

"5052" is used when corrosion resistance is required. It is 2.5% Mg, .2 CR .45(Si & Fe)

 

Where did you get the aluminum strip you used? If you just used a piece of scrap from something, it was probably "anodized" - a finish which makes it more corrosion resistant. The anodized surface might have interfered with your reaction.

[jdurg]

deionized water is just that: DE-IONIZED water. there are no ions dissolved in it. it is completely pure.

 

 

I have to totally disagree with you there. De-Ionized and Distilled water are COMPLETELY different. De-ionized water just means that any ions have been removed from the water, but non-ionic solutes can still be present. Distilled water is used when absolutely no solutes can be tolerated. De-ionized water is used when you don't care about non-ionic solutes, but you don't want any ions interfering.

[budullewraagh]

if by "totally disagree" you mean "disagree with the part about the complete purity" i understand. my regrets, i forgot about those non-ionic solutes at the time

[BenSon]

This is probably a stupid question but...

I thought there was a certain amount of ionized water in all water OH- and H+ ions, something like 10^-7(?) conc in neutral water. So does de-ionised water have no ions at all or is it just talking about removing all ions that haven't come from the water?

 

~Scott

[jdurg]

This is probably a stupid question but...

I thought there was a certain amount of ionized water in all water OH- and H+ ions' date=' something like 10^-7(?) conc in neutral water. So does de-ionised water have no ions at all or is it just talking about removing all ions that haven't come from the water?

 

~Scott[/quote']

 

They're talking about all ions that are not coming from the water itself. So all chlorides, nitrates, sulfates, bicarbonates, sodium ions, calcium ions, etc. etc.

 

And Bud, yeah, that's what I meant by 'totally disagree'. I just like to use strong words/phrases.

[umer007]

In the experiment of the reaction:

2Al(s) + 3CuCl2.2H20 (aq)---> 3Cu(s) + 2AlCl3 + 6H20

 

the products were later poured into a filter paper which trapped the copper precipitate. After the filter paper was dried, there was some green colour around the edges of the filter paper. I have been told that it was the compound Malachite. Could someone plz tell me where that malachite came from since it does not appear in the original reactant. Please provide a chemical eqn for it. I know that its chemical formula is Cu2CO3(OH)2, copper carbonate hydroxide. Does the carbon in this formula come from the air??From the carbon dioxide from the air??If so could someone plz provide a chemical eqn for it and sum more info...

 

Thx in advance

[BenSon]

I'd think that the carbon did come from the air as CO2 and heres my guess of the equation....

2Cu + 3H2O + CO2 = Cu2CO3(OH)2 + 2H2

 

~Scott

[umer007]

duz every1 agree wid this eqn? Is malachite formed in nature wid the same equation?

[BenSon]

Yeah i thought someone would probly be around by now to correct me (if im wrong). Malachite is malachite formed in the wild or in a lab..... naturally formed malachite would have lots of impurities though...

 

~Scott

[Tetrahedrite]

Yeah i thought someone would probly be around by now to correct me (if im wrong). Malachite is malachite formed in the wild or in a lab..... naturally formed malachite would have lots of impurities though...

 

~Scott

Yes, malachite is formed in nature the same way. There is an interest thermodynamic oddity here......

 

At atmospheric pCO2 (10^-3.5) the product is always malachite, Cu2CO3(OH)2.

 

When the pCO2 is increased (ie in carbonate solutions in the ground) to 10^-1.36 or above, a different compound is formed. This is called azurite, Cu3(CO3)2(OH)2, and rather than being green, it is brilliant blue.

[umer007]

So theres no chance of any azurite formed in this reaction since it was in done in a lab rite. Also what does that "p" infront of CO2 stand for? What are those atmospheric pressure (10^-3.5 and 10^-1.36) measured in?

 

Thx

[Tetrahedrite]

Yes, there is no chance of azurite forming under normal lab conditions, unless you are using carbonate solutions. The "p" means partial pressure in a gaseous mixture ( in this case, the atmosphere). It is like a concentration term for gases.

 

A pCO2 of 10^-3.5 is equivalent to around 0.032% CO2 in the atmosphere.

A pCO2 of 10^-1.36 is equivalent to around 4.37% CO2.

[umer007]

so 0.032% CO2 is present in the air, which is convrted to pCO2 10^-3.5 for the gases....rite. But are u sure about the hydrogen being released, is there any chance of telling hydrogen being formed by looking at the reaction or filter paper.

 

Also cud sum1 plz xplain to me how Copper (I) Chloride could have been seen on the filter paper after the experiment was done. How would it be formed?

[BenSon]

Yeah like i said that eqn was a guess if it is right then hydrogen would definately be released. About i dentifying the hydrogen you can see little bubbles but that would be realy unlikely because only small amounts are being formed. Do the reaction in a tt with a stopper as you remove the stopper hold a match over the top if it "pops" then you have hydrogen . About the CuCl being formed i suppose seeing if you had CuCl2 as a reactant and you didn't have enough Al then you could get some CuCl forming.

 

~Scott

[umer007]

well unfortunately my teacher told me hydrogen is not supposed to be released. He actually told me that the formation of malachite is actually a 2 step process so it wont work in one equation. If ne1 ever finds out plz post. O btw could CuCl have formed if the reaction was done fast in short amount of time, so kinda went uncontrolled and compounsd like CuCl couldve formed?