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Home Concept Builders Elements, Atoms, and Ions Isotopes Help Help 1

Isotopes - Questions 1 Help

An element is a type of atom. Hydrogen, carbon, and oxygen are three types of elements. They each differ in terms of the number of protons that are present in their atoms. The number of protons is known as the atomic number. It is a unique number for every element.

There is just one question in this Question Group. Each time the question appears, the answer options are presented in a scrambled order.
 

Version 1:
The atomic number of an isotope refers to the _____.
number of neutrons present in an atom
number of electrons present in an atom
number of protons present in an atom
number of protons and neutrons present in an atom
number of protons and electrons present in an atom

Like any course, a Chemistry course has a set of vocabulary terms that you just need to know. An understanding of the vocabulary becomes foundational to progress in the course. This question tests your knowledge of the term atomic number. The questions in the subsequent activities of this Concept Builder will test your ability to make meaning of it and use it. If you look up in the Fundamentals section of this page, you will see the definition of atomic number. But before you go answer the question, we suggest that you record a note in an accessible location that you can make frequent reference to until you gain a comfort with the meaning of atomic number.

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