How is the purity of substances important?​

Pure substances have the ability to form predictable outcomes from their chemical reactions. Chemists tend to use pure substances when conduction chemial research as impure substances can mess up their experiments.

periodic trends is an atom that gets larger as the number of electronic shells increase, the radius of atoms increases as you go down a certain group in the periodic table of elements. in general, the size of an atom will decrease as you move from left to right of a certain period.

answer by yourhope:

how do models compare to real-world objects?

d. most models represent a real-world object in a simpler way.

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