If an atom has a mass number of 23 and its atomic number is 11, then the number of protons is:
Correct answer: A. 11
- A. 11
- B. 23
- C. 12
- D. 22
Explanation
The atomic number of an element is defined as the number of protons in the nucleus of its atoms. Therefore, if the atomic number is 11, the atom contains 11 protons.
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About Fundamental Concepts of Chemistry
Mole calculations connect mass, number of particles and Avogadro's number, while balanced equations provide the mole ratios used in stoichiometry. Questions cover limiting and excess reactants, theoretical yield and percentage yield, including identifying which reactant is consumed first and comparing the actual product with the maximum possible product.
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