19. Elements are pure substance because . a. all their atoms have different atomic numbers
b. all their atoms have the same atomic number
c. all their atoms are linked to atoms of other elements
d. everything looks the same
Use the attached sheet of conversion factors to answer the conversion questions.
20. A measurement of 10.70 mm would be converted to cm.
a. 0.00107 c. 107.0
b. 1.070 d. 1070.

asking the goog might u get an answer

here's the link to your question!

explanation:

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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