What is the property that is most similar among all elements across on whole period called

 The atomic mass this is for edginuity kids 

This would be the atomic mass. Hope this helps!! :)

If we perceive our body as too fat even though our body is not we might diet until we think we aren't fat and if we perceive our body as too thin we might binge eat until we think we are average weight ( not too thin and not too fat )