apply chemical in copper coin needle repulsive and throw away of coin.. what is the name of chemical?
Answers
Answer:
Chemical Tests on Coins, Tommy Technetium YouTube Channel, 9/14/19.
There is quite a bit of chemistry involved in these tests. First, ammonia can be used to detect copper. This is because Cu2+ reacts with ammonia to form a dark blue colored complex:2
Cu2+(aq) + 4 NH3(aq) à Cu(NH3)42+ (Equation 1)
Thus, when a cotton swab soaked in 15 M ammonia is rubbed over the surface of a copper-containing coin, any Cu2+ on the surface causes the cotton swab to turn a blue color as a result of Equation 1.
Also, when coins that contain silver are rubbed with an ammonia-soaked cotton swab, a dark color often appears on the cotton. This color change is due to the formation of a black-brown colored silver complex on account of following reaction:3
Ag+(aq) + 2 NH3(aq) à Ag(NH3)2+ (Equation 2)
The video above shows the use of the reaction between dimethylglyoxime and nickel ions to detect nickel in coins. The chemistry of this reaction has previously been discussed on ChemEdX, 4 and therefore will not be covered here. The reader is referred to this article for further information about this test.
In addition to these tests, solutions of Cu2+ can be used to detect iron, zinc, and aluminum. Iron reacts with dissolved copper, causing solid copper to plate out on the iron surface:
Fe(s) + Cu2+(aq) à Cu(s) + Fe2+(aq)
Explanation:
this method is intended to determine the force to push a sewing machine needle through a standard material the method is applicable to all types of industrial sewing needles chemical