Hello, I'm a drummer so I please be gentle with me.

Please can anyone tell me what the difference is between these 2 gongs:
Gong 1 is 36" in size and tuned to C2/C1
Gong 2 is 36" in size and tuned to C2#/Cis
Also which gong is tuned lower?
Sorry for all the questions, great forum and I hope I posted in the correct part.