Are there choices? Because if there are that would help A LOT, but if there are no choices I can give some examples of physical properties, though there are MILLIONS, here are a few :) .
Physical property examples are: color, smell, freezing point, boiling point, melting point, attraction or repulsion to magnets and viscosity and density. If these are not options, please let me know :)
Have a great day, let me know if I can help with anything else, have a great day, and, if you have time, mark brainiest, I would really appreciate it, thanks! :D
        
             
        
        
        
Answer is valence electron, they all have total of 2 valence electron.
remember group number = valence electron
        
                    
             
        
        
        
Answer:
liquid, solid, and gas
Explanation: It depends where the molecules are moving. When a solid the molecules are vibrating and are all together, compact, the molecules are also very slow. When a liquid the molecules are moving back and forth, up and down, and are less compact, but moving faster. When a gas, the molecules move everywhere very quickly, moving super fast.
 
        
             
        
        
        
Answer:
Sodium chloride is added to the ice to lower the freezing point of the ice. Large crystals dissolve more slowly than small crystals. This allows time for the ice cream to freeze more evenly.
Explanation:
 
        
             
        
        
        
There is no way to know which reaction requires which catalyst. However, if you apply copper to a reaction where it does act as a catalyst, the rate of reaction will be much faster as it lowers the activation energy for successful collisions.