Need help! A copper penny dropped into a solution of nitric acid produces a mixture of nitrogen oxides...?
357536
First you will need to work out what the two half equations are (Hint, have a look at a table of standard reduction potentials - these not only give Eo for each half - equation, but also the half - equation of course). URL below if you need it.\n\nSecond, record the values of each half equation, then use the formula:\n\n Eo cell = Eo cathode - Eo anode \n\nto get the cell voltage. (If you are not sure how to do this, try the link below or re post)\n\nThirdly, use the Nernst equation (should be either in your lecture notes or your text, if not try Googling "Nernst Equation") to calculate Eo under the conditions stated in part b of your question.\n\nI hope this helps.
708721
Here is the right equation for nitric acid and sodium bicarbonate\n\n\nHNO3 + NaHCO3 ---> NaNO3 + H2O + CO2\n\nIf you do not like the sodium:\n\nHNO3 + HCO3(-) --> NO3(-) + H2O + CO2
24810
Cu + 2H2SO4 --> 2H2O + SO2 + CuSO4\nDouble the H2SO4 and the H2O.
170129
CuSO4 (s)  --H2O-->  Cu+2 (aq) + SO4-2 (aq)
527880
Use an eraser.It will take off tarnish and makes copper shine like new.For silver coins...Boil water in an aluminum pan ,add coins then add baking soda and remove from heat.Baking soda will cause a reaction and instantly clean the silver.Just rub w/ clean cloth afterwards.
564230
This is a selective way to produce cupper of cupper hydroxides by leaching hydroxide and elecrtowinnig as:\nCu(OH)2(s) = Cu+2(aq) + 2 OH–(aq) \nCu+2(aq) + 4 NH3(aq) = Cu(NH3)4+2(aq)\n\nand [Cu(NH3)4]2+ is better agent than [Cu(H2O)6]2+ in (aq) solutions for this.
326922
Another easy reaction:\n\nMg(s) + HNO3 ===========> Mg(NO3)2 + H2 (g)\n\nMagnesium reacts rapidly with nitric acid to make magnesium nitrate and hydrogen gas
676026
Wild guess here... a dihydrate of copper chloride.\n\nSecond guess would be copper sulfate, possibly from the manufacturing process.
418443
Copper can react with nitric acid on two different ways based on the concentration of nitric acid.\n\nIf cold and dilute nitric acid is used, then the reaction yields copper(II) nitrate, nitrous oxide(N2O) and water.\n\nCu + HNO3 ----- Cu(NO3)2 + N2O + H2O\n\nIf hot and conc. nitric acid(a stronger oxidising agent) is used, the reaction yields copper(II) nitrate, nitrogen dioxide(NO2) and water.\n\nCu + HNO3 ----- Cu(NO3)2 + NO2 + H2O\n\nP.S. - Balance the equations yourself(might take some time but use the oxidation no. method)
491198
Easy!! we did this in science a while ago, let the pennies soak in pure lemon juice, it works really well.
787695
The nitrate ion is a good oxidizer, meaning it is reduced and the other species it reacts with is oxidized. The flame test is color dependent on the oxidation state (or number of electrons) present in the metal you are analyzing. So I would imagine that if you were analyzing something like the copper (I) cation in the flame, the color would change due to the fact that the nitrate ion is causing another oxidized copper species to be produced, such as copper (II), which has a blue color. Hope this helps and let me know if you have any other questions!
513117
use a potato and two different metals as electrodes. The link will help you, do your own homework, or web searching atleast! it was the second link in google for g** sake!
535149
Actually the copper doesn't come directly from the solution...\n\nNot sure how much detail you want, but it does use electroplating.  This means that it uses electricity to plate metal on an object.  The stainless steel object is put on the "positive end" and a lump of pure copper is placed on the "negative end."  A low voltage is used because a high voltage plates too fast, and the layer will peel off quickly.  If copper is the plating, then the solution must be a fairly low-concentration copper sulfate (CuSO4) solution, meaning that copper is the only metal present in the electrochemical cell.  The negative end is called the anode, and this decreases in mass as its copper ions are taken to the positive end -- the cathode.  \n\nThis method of plating multiple metals is actually fairly common, because the properties of each one can be combined.  Nickel can be used for farm equipment and engines because it can withstand a lot of force, silver is used for decoration, chromium is used to withstand a lot of use (like a spoon).  Copper is able to conduct heat and helps food cook evenly.
723937
copper. because it can oxidize easier. That is why statue of liberty is green.
887687
Below is a link to a practical for finding the % copper in pennies.  The same method will work using brass in place of pennies.\n\nhttp://www.creative-chemistry.org.uk/alevel/module5/documents/N-ch5-17.pdf
339232
Yes, the reaction would spontaneously occur because Sn is higher on the activity series than Ag.\n\nSn(s) + 2AgNO3(aq) => Sn(NO3)2(aq) + 2 Ag(s)\nThe net ionic is\nSn(s) + 2Ag+(aq) => Sn+2(aq) + 2 Ag(s)\n\nI don't remember the oxidation number for Sn.  2 sounds about right.\n\nIt would turn a silver nitrate solution to a tin nitrate solution, and you'd see metallic silver precipitate out.
183774
oxidized copper is green