Flashcard 13-Chemistry Flashcard Set for the HESI Exam
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\[10\]
Explanation:
Oxygen has an atomic number of \(8\), meaning it has eight protons. The isotope \(\text{}^{18}_{\phantom{1}8} \text{O}\) has a mass number of \(18\), and subtracting the atomic number from the atomic number gives \(10\) neutrons.