Silver Tarnishing Lab

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The tarnishing of silver is due to a chemical reaction between silver and hydrogen sulfide, producing silver sulfide and hydrogen gas. The balanced chemical equation is
2Ag (s) + H2S (g) → Ag2S (s) + H2. This is a single replacement reaction. This reaction most commonly occurs through contact with hydrogen sulfide in the air - although direct contact with substances that contain sulfur can cause tarnishing.
Silver tarnishes very quickly when it is exposed to air that contains high levels of ozone, sulfur, or hydrogen sulfide. Silver tarnish appears as a discoloring over the surface of the metal. Rather than the usual shiny or soft appearance of silver, the item’s color could range anywhere from pale yellow to black. The tarnish usually does not cover the silver evenly; it often appears in
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Depending on how often handled and the extent to which it is left exposed, the tarnishing will occur at a faster rate. However, many sterling silver products, especially jewelry, have a protective anti-tarnish plating, a lacquer that bonds to the silver to prevent tarnishing. Tarnishing can occur anywhere, but the reaction will begin sooner and continue at a faster rate if there is a higher concentration of ozone, sulfur, or hydrogen sulfide in the air. Sometimes, jewelry makers will drop silver in baths of sulfur to create an aged look; this tarnishing process only takes a few seconds.
Many items of silver can tarnish, including silverware, flatware, jewelry, display and art pieces, and other common objects. It is believed that tarnishing occurs at a faster rate in the present day due to the increased presence of H2S in the atmosphere via the burning of fossil fuels.
While rust will corrode metals, tarnish is self-limiting. The layer of tarnish will seal and will actually prevent deeper layers of the silver from tarnishing. For this reason, only the top layers of a silver item will

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