HESI A2 Exam Prep 2026

Real HESI A2 Questions.
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Practice with exam-accurate HESI A2 questions that match the real test in format, difficulty, and logic. Trusted by students accepted into nursing programs across the United States.

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Total Test Time
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About Atomic Structure

Discover how to calculate the atomic number of an element using protons and atomic mass. Learn this concept for HESI A2 Chemistry with clear examples.

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Atomic Structure HESI A2 Practice Questions

Free Atomic Structure practice questions for the HESI A2 exam with detailed rationales.

Question 1 of 2

An unknown element is found to contain 45 protons and has an atomic mass of 64. What is its atomic number?
19
45
64
It cannot be determined