Complete Atom Set - 1,2,3,4,5, and 6 Bond Atoms! (Compatible with most retail sets)

This set is meant to be printed with PLA, with the exception of the long bonds, which should be printed with TPU to ensure the flexibility required to make certain molecules. The colors I used is as follows: 

• Oxygen (Red): 2 bonds 
• Hydrogen (White): 1 bond 
• Carbon (Black): 4 bonds 
• Nitrogen (Blue): 3 bonds (can also form 4 bonds in certain cases, e.g., in ammonium ion)
• Iodine (Purple): 1 bond (can form up to 7 bonds in specific compounds, but typically 1) 
• Chlorine (Green): 1 bond (can form up to 7 bonds in specific compounds, but typically 1) 
• Sulfur (Yellow): 2, 4, or 6 bonds 
• Generic Metal (Grey): Variable bonding depending on the metal and its oxidation state 

The scale is 1.75cm = 100pm. 

I'd be happy to add anything else needed.