配方类型: |
METALS AND THEIR TREATMENT |
配方说明: |
Cleaning Old Coins |
配制方法: |
Use a small stainless steel pan as an anode and the corroded coins as cathodes. The pan is filled with a 2% solution of sodium hydroxide, and the coins dangle from alligator clips into the bath. When a direct current from a small battery charger (12 volts, 950 milliamps) is applied across the circuit the coins literally clean themselves. |
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