How are ball and sticks and space filling are similar ?

Ball and stick models are three-dimensional models where atoms are represented by spheres of different colors and bonds are represented by sticks between the spheres. ... Space fill models are similar to ball and stick models in that they are three-dimensional models that represent atoms as colored spheres.

out of these options:

ability to burn paper

pure sodium reacting violently with water

the boiling point of water

helium does not tend to react with anything

i would say this is a physical property:

helium does not tend to react with anything

why? :

i said helium does not tend to react with anything because well, it reacts to ! but ability to burn paper, pure sodium reacting violently with water, & the boiling point of water are chemical or

physical properties: the properties of a substance that can be observed without changing the chemical makeup of the substance

chemical properties: properties of a substance relating to the chemical nature and reactivity of the substance