How to destroy the security key 

Last year, I had trouble a couple of times due to the keys still being widely used in Europe. 
Since I became an adult, I don’t recall I had a door with a physical key in Korea which means I never used to have a key around me. (Thank god I never lost a car key yet…)  No wonder I am terrible at managing them. 
I stupidly left the key to the main entrance in Korea when we came back for Christmas holiday. My landlord seemed pretty sensitive about that key. It took me about a month to get permission to copy that key while emailing back and forth to explain why do I need more than one for the main entrance. 
She got upset when I told her I left one copy key in Korea so I told her sorry for being stupid and I can show her the evidence I destroyed it so she can assure the other key was walking around in this earth. She said no need at that time but she was asking the evidence, so I decided to have some fun with it.  Here we go. 

-Destroy it physically 
Simply hammer it.  Thanks Minh for recording. 
Aiming it was not that easy. Took about 5 mins. 

-Destroy it chemically 
We made an electrolytic cell using my existing knowledge o f chemistry. 
+: The key 
-: Aluminum plate 
using 12 V for power source. 
Left it for about 3 days. 

Table salt was used for electrolyte. 
Cl2 will form and it will damage the key. 

We were cautious about the Cl2 gas. We wanted to make it sure it’s under safe environment. We were wearing masks and goggles whatever we could find. This was not necessary. Most of Cl2 gas remained in the solution. 

The mass of the key changed 17.01 g to 14.53 g. The mass change was 2.48 g 
Cl2 was really yellow green!! 
The key turned into pink which might be caused by copper. 

Thanks Minh and my eccentric, genius friend Joe. 
This was fun. 

#key
#chemistry
#electrolyticcell
#chemistrylab
#scienceathome
#chem#is#try #londonlockout