A neutral atom of a potassium isotope has 19 protons and 21 neutrons in its nucleus. What are the atomic number and mass number of this atom, respectively?

A) Atomic number: 21, mass number: 40

B) Atomic number: 19, mass number: 21

C) Atomic number: 19, mass number: 40

D) Atomic number: 40, mass number: 19

Atomic number and mass number Knowledge-Based Practice

Chemistry · Atomic Structure · Chemistry · Atoms & Subatomic Particles

1 Chemistry practice questions on Atomic number and mass number. Questions that assess core concepts and understanding.

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Atomic Structure · Chemistry

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