Answer:

• B. proton and electron

Explanation:

• Neutral atoms of an element contain an equal number of proton and electron. The number of protons determines an element's atomic number (Z) and distinguishes one element from another.

ANSWER:

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Which subatomic particles particles are equal to an element's atomic number?

• B. proton and electron

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EXPLANATION:

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• Atomic number is always equal to number of protons in an atom in its stable state and also equal to number of electrons.

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