2.2.3 - Atomic Number and Mass Number
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Practice Questions
Test your understanding with targeted questions
What does the atomic number represent?
💡 Hint: Think about what defines an element.
How do isotopes differ from one another?
💡 Hint: Consider the components of the nucleus.
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Interactive Quizzes
Quick quizzes to reinforce your learning
What is the atomic number of an element that has 11 protons?
💡 Hint: It's the same as the number of protons.
True or False: Isotopes of an element always have the same mass number.
💡 Hint: Focus on what makes isotopes different.
1 more question available
Challenge Problems
Push your limits with advanced challenges
A neutral element has an atomic number of 15 and a mass number of 31. How many neutrons does it have?
💡 Hint: Remember the formula for mass number.
If an isotope of iodine has a mass number of 127 and the atomic number is 53, how many neutrons does it have?
💡 Hint: Use the same subtraction method as before.
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