metallic gold is shining yellow but gold sol is light pink. why?
83109
Metallic gold offers a reflective surface which absorbs some of the light in the blue-green range, thus gives a yellow shine. \n\nA sol is a precipitated colloid. Particle size is too small to be registered by the naked eye, and the reflective quality of solid gold becomes a scattering quality. There still is some absorption in the same color range, but particle size may cause certain wave lengths of light to be eliminated.
1082494
White gold is an alloy of gold that contains another metal, like platinum, causing it to look more like silver.  While gold always contains less actual gold than pure gold, but may be more valuable on an ounce basis if the alloy metal is more valuable than gold.  One common use of white gold is to make the metal much harder than 24 carat gold so that it is more resistant to dents and other damage.
787554
Gold is not very reactive because its unpaired 6s electron is at a lower energy level than its many paired 5p and 5d electrons.  So even though gold would like to give up its unpaired electron or accept a partner for it, it usually can't because of the stability of the higher energy electrons that are already paired.
206108
You would not want to plate white gold with platinum, you should do this with regular gold for the simple fact that yellow gold is cheaper than white gold so you would be cutting your overheads.
959501
It is usually the metal. The metal responsible for the color can be the cation, like Cu+2 in blue CuSO4, or it can be in the anion, like CrO4= in yellow Na2CrO4. Sulfur is a nonmetal, but its presence in compounds intensifies the color. CuS is an opaque dark brown. The nonmetallic ion thiocyanate, CNS-, reacts with yellow ferric [iron(III)] ion to form a brilliant red complex.\n\nAdditional detail: The metal, of course!
1154066
It is not due to the chemistry of copper or gold.\n\nIt is due to the electronic band structure. The two metals unusually have a band structure that causes them to absorb light at certain frequencies rather than reflecting it.
939721
If it's metallic, it could be sodium or potassium.
267064
yes gold is based on a 24 part scale for example when u have 14 kt gold u have 14 parts gold and 10 parts other material generally your gold vendors use nickel in white gold and for yellow gold generally copper zinc or sometimes a palladium so anything under 24kt gold is mixed with other material in one hand to cut the gold and in the other to make the gold stronger due to the malluability of gold.
336935
White gold refers to an alloy of gold and other white metals such as silver, palladium, or nickel. The natural colour of white gold is light gray, so jewelry made of white gold is typically coated in highly reflective rhodium (sometimes coated in platinum and palladium), adding a more brilliant shine. Palladium and silver alloys are of higher quality than nickel and are sometimes not coated with rhodium. The purpose of plating is to add luster to grayer jewelry, as well as to prevent oxidation of some of the metals found in the alloys. White gold is not platinum, but is used as a cheaper alternative, usually costing one-third as much as platinum
329489
A mixture of two metals is called an "alloy."\n\nThere is *no* chemical reaction (the gold atoms are not reacting with the silver atoms).  It's just a melted mixture.\n\nWhite gold is an alloy of gold with other white metals, like silver, nickel, or palladium (source below).
1099415
I don't know how you are precipitating out the gold, but I don't think a colorimetric test for gold in solution is possible.  It is non-reactive and does not ionize.  Given that gold has filled upper electron orbitals, you might be able to run a UV-VIS spectrum and get some UV absorption for solvated gold versus clean aqua regia.  The UV apsorption is probably going to be in the lower UV wavlengths, and it might not be possible to differentiate between trace levels of gold and trace levels of transition metal impurities.\n\nIf you are precipitating the gold by an equilibrium process, just load up on your precipitation compound to push the equilibrium as far as possible to one side.  Another possibility is to electrolytically remove any trace gold from the aqua regia.  Sorry I don't have any better suggestions.
87628
Gold is not naturally white so I would assume it is false unless coming from a very reputable jeweler.
669187
NO white gold has different kind of alloys in it , wen u mix it u wont get PROPER COLOR OF THE GOLD it will look like brass and wen u mix it and wen u are working on it will give u many problems like breakaga and all.\ntake care be carefull\nRAHUL :)
359049
potassium permanganate becomes pink if it is diluted more and more.\nand it is pink because of d-d transition.
337388
rose gold is alloyed with copper, white gold is alloyed with silver. The karat value of the different pieces would determine their value in a gold market. In a retail market, hallmarking, craftsmanship, and supply and demand would dictate the values of each type of piece.
1039579
http://en.wikipedia.org/wiki/Gold\n\nGold can be mixed as an alloy with other substances to get other colors.  Pure gold is, well, gold-colored.
25132
If you want to identify brass versus gold, try using some ammonia solution or vinegar on the metal. Brass has oxides which will be dissolved and the brass will come out much brighter. Gold does not oxidize and will not react. Highly polished brass will not have an oxide coat to remove, so you can test it by immersing it in a solution with 2/3 vinegar and 1/3 hydrogen peroxide solution, and leave it for more than fifteen minutes. If it is brass and not gold, the solution will begin to turn green as the copper in the brass begins to dissolve. Again, gold will not react.