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Home Concept Builders Elements, Atoms, and Ions Isotopes Help Help 13

Isotopes - Questions 13 Help

Isotopes include two or more versions of an atom of a given element that have the same number of protons but a different number of neutrons. The isotope in this question is a charged atom, also known as an ion. They have unequal numbers of protons and electrons. An isotope symbol communicates information about the element (specifically, the symbol), the atomic number of that element, the mass number of the specific isotope of the atom, and the electrical charge on the ion.

There are three similar versions of this question. Here is one of those versions:
 

Version 1:

An isotope contains 21 protons, 23 neutrons, and 18 electrons. Construct the symbol for the isotope.

Activity 3 - Isotope Symbols II - is all about constructing the isotope symbol from information about the atom. Each atom is a charged atom or an ion. Refer to the Fundamentals section (above) to acquire the basic information. Then study the graphic below and the information that follows.



You will have to make use of the periodic table to associate the element name with the atomic number. The number of protons and the number of electrons can be used to determine the ion charge.

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