Question

why atom is a neutral particle

Answer 1

atoms are not neutral it react... if it's shell incomplete, but it neutral in case of itself affect... and it's because their no. of proton and electron is same...

Answer 2

We defined “atom“ as a neutral particle consisting of neutrons, protons, and electrons. ... Atoms, as a whole, are considered neutral because the atom of any element has equal number of protons (positively charged particles) and electrons (negatively charged particles), canceling out and making the atom neutral as whole.
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