{"id":1860,"date":"2012-11-28T22:23:31","date_gmt":"2012-11-28T13:23:31","guid":{"rendered":"http:\/\/nishiko55.com\/eq\/wordpress\/?p=1860"},"modified":"2012-11-28T22:25:15","modified_gmt":"2012-11-28T13:25:15","slug":"24-oct-2012-10%e5%86%86%e7%8e%89-10yen-coin","status":"publish","type":"post","link":"http:\/\/nishiko55.com\/eq\/?p=1860","title":{"rendered":"Object #29 10\u5186\u7389 10yen coin"},"content":{"rendered":"

\"\"<\/a>
\n24 October<\/p>\n

\u3054\u8cea\u554f:<\/strong>
\n10\u5186\u7389\u3092\u304a\u9162\u306b\u6d78\u3051\u308b\u3068\u304d\u308c\u3044\u306b\u306a\u308b\u306e\u306f\u3069\u3046\u3057\u3066\u3067\u3059\u304b\uff1f<\/p>\n

\u56de\u7b54:<\/strong>
\n\uff11\uff10\u5186\u7389\u306e\u8868\u9762\u306f\u3001\u7a7a\u6c17\u4e2d\u306e\u9178\u7d20\u306b\u3088\u3063\u3066\u9178\u5316\u3055\u308c\u3001\u9178\u5316\u9285\uff23\uff55\uff2f\u306b\u306a\u3063\u3066\u3044\u307e\u3059\u3002
\n\u3053\u308c\u3092\u304a\u9162\u306b\u5165\u308c\u308b\u3068\u3001\u9178\u5316\u9285\u3068\u9162\u9178\uff23\uff28\uff13\uff23\uff2f\uff2f\uff28\u304c\u53cd\u5fdc\u3057\u307e\u3059\u3002\u53cd\u5fdc\u306b\u3088\u308a\u3001\u9178\u5316\u9285\u306f\u9162\u9178\u9285\uff23\uff55\uff08\uff23\uff28\uff13\uff23\uff2f\uff2f\uff09\uff12\u306b\u306a\u308b\u305f\u3081\u306b\u3001\u6eb6\u3051\u3066\u8868\u9762\u304c\u304d\u308c\u3044\u306b\u306a\u308a\u307e\u3059\u3002 \u3053\u308c\u306f\u9285\u672c\u6765\u306e\u8272\u3067\u3059\u3002 \u307e\u305f\u3001\u3053\u306e\u53cd\u5fdc\u306f\u3001\u6025\u901f\u306b\u304a\u3053\u308a\u3001\uff11\uff10\u5186\u7389\u3092\u5165\u308c\u308b\u3068\u3001\u8272\u306f\u307f\u308b\u307f\u308b\u5909\u3063\u3066\u304d\u307e\u3059\u3002
\nhttp:\/\/www.mizkan.co.jp\/customer\/qa\/cid_detail_000020.html<\/a><\/p>\n

Question<\/strong>:
\nQuote from: chris on 25\/12\/2006 20:30:06
\nI have found that dumping old tarnished (brown) copper coins in vinegar (with a little added salt (NaCl)), results in the coins becoming pink and shiny within a few minutes.
\nWhat is the nature of the chemical reaction that is obviously taking place, and why do the coins go brown in the first place? By contrast, a copper roof goes green yet must be exposed to similar chemistry to a coin.<\/p>\n

Chris<\/p>\n

 <\/p>\n

Answer<\/strong>:
\nBlack copper oxide CuO reacts with acetic acid CH3COOH (inside vinegar) forming copper acetate Cu(CH3COO)2 and water:
\nCuO + 2CH3COOH –> Cu(CH3COO)2 + H2O
\nA similar reaction happens with Cu(OH)2, CuCO3, Cu2CO3(OH)2 ecc.
\nThe copper acetate is water soluble and dissolves away, leaving a clean copper metal surface.
\nBy the way: copper acetate forms very beautiful dark emerald green cristals when dried.
\nhttp:\/\/www.thenakedscientists.com\/forum\/index.php?topic=6240.0<\/a><\/p>\n

\"\"<\/a>
\n14 November<\/p>\n

\"\"<\/a>
\n15 November<\/p>\n

\"\"<\/a>
\n16 November<\/p>\n

\"\"<\/a>
\n