Shell of an atom is positively charged why

atoms was the realization that electrons are arranged in shells that surround a central positively charged nucleus. ... Each ion thus attains a closed outer shell of electrons and takes on a spherical shape.

Explanation:

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1 a

2 d

3 a

4 c

explanation:

answers: to make sure that all of the broken pieces of tablet were added to the water, to allow for fair comparison of all three trials, with different particle sizes to avoid experimental error