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Chemistry redox conceptual question?

The black tarnish that forms on a silver ornament is silver sulfide, Ag2SThe tarnish can be removed by wrapping the silver ornament with a piece of aluminium foil and placing it in a solution of NaHCO3 (baking soda) to allow the flow of ionsHow does the aluminium foil help in removing the tarnish??? And NaHCO3, sodium bicarbonate is used to allow the flow of ions in this caseCan we use any salt of bicarbonate anion instead of NaHCO3?

Answer:

use your stock airbox and put in a KN filter that fits your stock airbox is the best way.
We have used the polished alum pipe before, plastic corragated drain pipe, dryer vent hose/ducting, PVC plumbing pipes, elbows, couplers, etc sheet metal for air boxes, plastic, plexiglass, lexan for air boxes
There are relatively few soluble carbonates, but you could also use KHCO3 or K2CO3 or any soluble carbonateBut you don't even have to use a bicarbonate compoundYou can use any electrolyte Actually NaCl will work much better than sodium bicarbonateAluminum has a natural coating of Al2O3The presence of chloride ion breaks down the passivating layer of Al2O3, forming AlCl4^- and exposing fresh Al metal to the silver tarnishIt also helps to warm the solution to speed up the reaction2Al(s) + 3Ag2S(s) - Al2S3(s) + 6Ag(s) The reaction is a redox reaction in which aluminum metal (which is higher in the activity series than silver) will replace silver in a single replacement reactionAluminum metal is oxidized, while silver is reduced to silver metalThe electrons move from aluminum to silver The charged ions facilitate this electron transferThe sulfur ends up on the aluminum foil and silver metal is left adhering to the silver ornament.

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