copper

  1. R

    Copper electrlysis

    Set up 2 copper electrodes in beaker- 50/50 muratic acid water- 12v across electrodes-ques.-what copper product can i expect at each electrode?
  2. A

    What's the best flux liquid for soldering copper onto stainless steel, HCl or H3PO4?

    What's the best flux liquid for soldering copper onto stainless steel, HCl or H3PO4, with how many percent concentration of each ? How's logical explanation on solder sticking process will actually work some suggest Phosphoric acid better, actually I tried both works, ...many thanks in advance !
  3. A

    cooper powder from copper wires

    Hi, I am trying to get cooper powder from some cooper wires. I have performed following steps after searching from Internet: 1- 10gm of cooper wires are mixed with 50 ML of Nitric acid 2- When cooper is completely dissolved i get blue solution 3- Mixed 150ml of water in solution 4- Placed a...
  4. B

    Spectroscopy of Copper Sulphate

    Hi Everybody, I scanned 5 concentrations of copper (II) sulphate using a spectrophotometer. The concentrations I used are from 0.06 to 0.3 molar. I get two peaks in absorbance. Why are there two peaks? Also, the peak at 290nm has a variation in its maximum wavelength. This is what I am...
  5. J

    oxidation?

    I am by no means a chemist but I am curious about oxidation on copper what causes it and is it a process that can be reversed while returning the metal to its original color before oxidation?
  6. D

    Is this MO diagram correct? Copper 2+ (18-crown-6 ether) complex

    Hello all! Ive been a long time lurker of these forums, but finally registered to seek help for a problem im stuck on! Ive constructed the following http://i.imgur.com/v2ldA7u.jpg MO diagram for a complex im trying to synthesize. Am I on the right track? The splitting and degeneracy of d...
  7. J

    Just a few reactions with copper...

    By reaction between 25 g of heterogeneous aluminum, zinc and copper mixture and sodium hydroxide solution, 9.73 cubic dm of hydrogen is released at STP conditions. By reaction between hydrocloric acid and 20 g of newly formed sample, 14.48 cubic dm of hydrogen is released. Determine the mass of...
  8. R

    Help making Copper Salicylate

    Hello. I'm in need of help from some chem geeks :). I'm a Home Schooling mama and my 14 year old daughter is learning chem. We are trying to make Copper Salicylate, for a vitamin & mineral supplementation experiment, and all we can find about it, on Wiki, is that it is a mixture of copper...
  9. S

    Finding molar mass of copper

    Hi, in my experiment I determined that copper has a specific heat capacity of 0.275 J/(g* Celsius). How do I approximate it's molar mass using this piece of information?
  10. A

    Copper electrolysis experiment

    I have a 1part sulphuric acid 4parts tap water pregnant leach solution (from old copper mine tailings). If I were to set up an electrolysis type experiment with a lead anode and a copper cathode should I expect all the metals (i.e. copper, iron, cobalt) in the solution to be deposited onto the...
  11. B

    Oxidising copper cable

    I am attempting to re-produce the effects of resistive heating upon connection points within electrical circuits in lab conditions. In normal circumstances, this process occurs over a number of years and the localised heat generated results in oxidisation of the cable & terminal, increasing...
  12. G

    Copper Salicylate/Cupric Salicylate solubility problem

    Hi all, I'm having a few problems getting my copper salicylate to dissolve properly. All my preliminary research said that the powder form is soluble in water. However upon my inital testing i found that although some did dissolve it left large amounts of sediment. I tried vortexing the mixture...
  13. S

    Mass of Copper in Penny! HELP!!

    We preformed an experiment in which we dissolved a 2.2453g penny in 20mL nitric acid. The dissolved penny and acid was transferred to a 100mL flask and diluted with distilled water. 25mL of this solution was pipetted to another 100mL flask, 10mL of ammonia was added, then it was again diluted to...
  14. P

    Please Help With An Electrochemical Calculation.

    Hi, Please help me with this, I greatly appreciate any assitance; An electrochemical cell is given, one containing an 0.1M CuSO4 solution and the other one containing an 0.1M ZnSO4 solution. Then, the Cu ion concentration is decreased by adding an Ammonia solution NH4OH into the CuSO4...
  15. M

    What is the reaction mechanism for the formation of copper (II) carbonate (verdigris

    What is the reaction mechanism for the formation of copper (II) carbonate (verdigris patina) from copper, water, carbon dioxide, and oxygen? Anyone know the exact mechanism to this reaction? Does the water attack the carbon dioxide first, forming bicarbonate?
  16. P

    copper and sulfur ?

    What happened if you mix the minerals copper and sulfur and add warm water ? ( say 101degrees ) Pawn
  17. A

    Calculate the Mass Fractions of Gold and Copper

    A 9.40g wedding band is made up of gold and copper, and has a 4.382x10^22 atoms. Calculate the mass fractions of gold and copper in this 18-carat gold alloy. I have gotten this far: 1) (Au) = gold = x (Cu) = copper = y 9.40g = x + y 2) Ntotal = 4.382x10^22...
  18. B

    Etching copper alloys with copper chloride

    My name is Ben Renard. I am a model railroad enthusiasts. One of the aspects of the hobby that I have dove into recently is photo etching printed circuit boards and thin parts from copper alloys. The basic process begins by coating the metal sheet or PC board with a etchresist film that when...
  19. T

    Copper Carbonate Observation

    I am a 3rd year chemistry student and I came across an interesting phenomenon, when you add 20 mL of 10M HCl to 10 mL of 0.30M CuSO4, you of corse get the bright yellow CuCl4 anion. If you add excess dissolved sodium carbonate (60 mL of 2M), instead of coming out of solution, it forms a deep...
  20. A

    Electrochemistry. Electrolysis CuSO4 copper electrodes

    Hi everyone, I'm doing an experiment on electrolysis of CuSO4 using copper electrodes and there is something that confuses me a lot The thing is that the concentration of the electrolyte should remain the same and so does the copper ions. However, when measuring the current, it increases...